Antibiotics are
not an integral part of treating CKD, but their use is essential if your
cat has a bacterial infection. In CKD cats, these are most commonly:
The good news
is that although infections may make your cat sicker, and in the
worst case may cause your cat to crash, getting the infection under
control can make your cat feel much better and may even lead to an
improvement in blood test results.
Length of Treatment
Most courses of
antibiotics last for 5-14 days.
However, if
your cat has a
kidney infection
(pyelonephritis), a longer course is
necessary, for up to 4-8 weeks. Some urinary tract infections also need a longer course of around
four weeks.
Although most
antibiotics start to show an effect within 48 hours, once you begin a
course of antibiotics it is very important that you complete the course,
otherwise antibiotic resistance may occur (see immediately
below).
If your cat
reacts badly to an antibiotic, contact your vet and discuss switching to
another type.
Antibiotic Resistance
Antibiotic
resistance does not mean the cat is resistant to the antibiotic, or
showing a bad reaction to it. Antibiotic resistance means the bacteria which are causing
the infection have developed an immunity to the antibiotic, so will not be
killed by it.
US Centers for Disease Control and Prevention
explain more about antibiotic resistance.
One reason
antibiotic resistance occurs is if too short a course of antibiotics is
given. This can mean the bacteria are weakened, but not all of them are killed,
and the stronger bacteria which were not killed off will regroup and develop resistance to the
antibiotic. The next time these bacteria are exposed to that antibiotic,
it will not kill them.
Ideally you want to give an antibiotic to which you know the bacteria will
respond. The best way to do this is through a
culture and sensitivity test, which identifies to which antibiotics
the bacteria are susceptible. This enables you to only give an antibiotic
which is known to be effective for your cat's infection.
Using Probiotics in
Addition to Antibiotics
Antibiotics aim
to eradicate the bacteria causing the infection. However, they will also
eradicate "good" bacteria which normally protect the body from infection.
Therefore, when giving
antibiotics, you may need
to re-balance the bacteria in the gut with
probiotics
("good" bacteria).
Amoxicillin and Clavulanate
(Clavamox or Augmentin, Synulox or Noroclav)
Amoxicillin is
an antibiotic in the penicillin family. It may be used alone, but for
cats it is often combined with clavulanate, an inhibitor of an enzyme
produced by bacteria (this enzyme could render the amoxicillin inactive if
the clavulanate were not present). Combining the two means more bacteria
should be killed than amoxicillin alone could achieve.
Trade names
include Clavamox (veterinary formulation) or Augmentin (human formulation)
in the USA and Synulox or Noroclav in Europe.
This antibiotic
is used for upper respiratory infections, urinary tract
infections and dental infections. In the UK it tends to be the antibiotic
which most vets prescribe routinely for many infections.
In CKD cats it
is often prescribed for urinary tract infections.
Amoxicillin and Clavulanate Formulations
There are a number of different formulations available, including
Clavamox, which comes as a 62.5mg tablet,
a 62.5mg chewable flavoured tablet and an oral suspension with 62.5mg per
ml; and
Noroclav injectable.
Synulox in the UK comes in flavoured
pills (known as "pink sweeties" in our house) which Harpsie would happily
eat out of my hand.
Amoxicillin and Clavulanate Dosage
For amoxicillin alone (i.e. without clavulanate),
Pet Place states "The dose of
amoxicillin ranges from 5 to 12 mg per pound (10 to 25 mg/kg) two or three
times a day orally.
This would mean that a 10lb (4.5kg) cat would receive 50 to 120 mg two or
three times a day of amoxicillin.
Referring to
the Canadian amoxicillin 100mg tablets,
Drugs talks
about "a dosage rate of 11-22 mg/kg once daily" for cats, which is broadly
similar to the Pet Place recommendation. However, it also says "In severe
urinary tract and gastrointestinal tract infections requiring high
concentration, the above dosages should be doubled."
This may not be
appropriate for CKD cats.
Drugs says of the Canadian 100mg tablets
"Since Amoxicillin 100 is excreted mostly by the kidneys, reduce the
dosage for patients with renal impairment in proportion to the degree of
loss of renal function." Urinary tract infection: how to diagnose and treat
correctly (2003) Brovida C
Presentation to the
World Small Animal Veterinary Association World Congress
outlines how to modify the dosage for cats with kidney disease.
For Clavamox (which contains both amoxicillin and clavulanate),
Pet Place states "the most common dose of
clavamox used in dogs and cats is 6.875 mg per pound (13.75 mg/kg) every
12 hours." This would mean that a 10lb cat would receive 68.75mg twice a
day, slightly more than that recommended by
Drugs, which says "The recommended dosage
is 62.5 mg twice a day."
Be guided by
your vet as to the most suitable dosage for your cat.
Pet MD says of amoxicillin "This drug should
be given for at least 7-10 days to be effective."
Drugs says of Clavamox "The maximum
duration of treatment should not exceed 30 days."
Amoxicillin and Clavulanate Side Effects
Unfortunately this medication can cause loss of appetite, lethargy,
drooling, vomiting and diarrhoea in some cats, and CKD cats appear to be
more likely to experience more than one side effect, according to.
Pilot study of side effects and serum and urine
concentrations of amoxicillin-clavulanic acid in azotemic and non-azotemic
cats (2020) Benson KK, Quimby JM, Dowers KL, Sieberg LG,
Daniels JB, Langston CE, Lunghofer PJ & Gustafson DL Journal of Feline
Medicine and Surgery22(8) pp729-735, which states "The data suggest that cats with
azCKD have altered pharmacokinetics of amoxicillin, which may contribute
to an increased incidence of multiple side effects."
My Karma did not have CKD but she just could not tolerate this treatment
for more than a few days. Apparently it is not uncommon for cats to be
fine for a few days on this antibiotic but then exhibit side effects
towards the end of the course.
Giving food
before you give the antibiotic may help, as may probiotics (see
above),
but if not, contact your vet to see if you should switch to a different
antibiotic. Your vet may wish to try amoxicillin without the clavulanate,
or may wish to use a different type of antibiotic. Do not simply stop
giving the medication because this may make the infection return
(see above).
Enrofloxacin
(Baytril)
Enrofloxacin
belongs to the fluoroquinolone family of antibiotics. Trade names include
Baytril and Zeden. Like amoxicillin, it is a broad spectrum antibiotic (i.e. it
works on a wide range of bacteria). In high doses, it may in rare cases
cause blindness.
Enrofloxacin is
a powerful antibiotic and is not normally used for minor infections.
Summary of product characteristics says
"Fluoroquinolones should be reserved for the treatment of clinical
conditions which have responded poorly, or are expected to respond poorly,
to other classes of antimicrobials. Wherever possible,
fluoroquinolones should be used based on susceptibility testing."
Enrofloxacin is
a popular choice for kidney infections (which can be difficult to treat), where it
appears able to reach bacteria deep
in the kidneys which less powerful antibiotics cannot touch. One of my
cats was prone to kidney infections and enrofloxacin saved his life on
several occasions.
The manufacturer
states that this class of antibiotics is not considered to be
harmful to the kidneys, and that tests on dogs indicated no evidence of
kidney damage even at high dosing levels. However,
ISFM consensus guidelines on the diagnosis and
management of feline chronic kidney disease(2016)
Sparkes AH, Caney S, Chalhoub S, Elliott J, Finch N, Gajanayake I,
Langston C, Lefebvre H, White J & Quimby J Journal of Feline Medicine &
Surgery18 pp219-239 state "Avoid enrofloxacin in cats with CKD due to increased risk of
retinopathy at standard therapeutic doses.” See
below for more on this.
Enrofloxacin Formulations
Enrofloxacin in widely available in 15mg tablet form. It doesn't taste very nice, so
it is also available as a chewable tablet called Taste Tabs.
There is an injectable form of enrofloxacin but it is only approved for dogs.
Some people have used it for cats, but this is not recommended because there is a small risk of an
abscess at the injection site. Occasionally, however, a vet will start the
treatment plan with an injection and then the course of treatment will
continue at home with tablets. Plumb's Veterinary Drug Handbook (7th Ed.)
says "Use of the canine or bovine injectable products in cats is
controversial and may result in significant adverse effects. Parenteral
administration in cats at doses less than 5 mg/kg have reportedly caused
ophthalmic toxicity (blindness)."
Enrofloxacin Dosage
The official
recommended tablet dose in most countries is 5 mg of enrofloxacin per kg of
bodyweight per day.
For the
injectable version, the usually recommended dose is 1ml per 5 kg of cat,
which is the equivalent of 5mg per kg of bodyweight.
This is the
recommended total daily dose for cats of the following weights:
Cat Weight lb
Cat weight kg
Recommended dose mg
5 lb
2.27
11.25
8 lb
3.64
18.20
10 lb
4.50
22.5
The dosage of
5mg per kg of bodyweight was introduced because of the risk of higher
doses causing blindness in cats. The issue did not arise until the
recommended dosage limits were dramatically increased, and once the issue
became known, the reduced dosage of 5mg per kg daily was introduced. See below for
more on the
blindness issue.
For the
overwhelming majority of cats, this is a safe dosage, because, according
to
Baytril, 16 of the 17 cats who developed blindness were given doses six to ten times higher than
the recommended dose. However, the other cat in the study who became blind had received a dose of only 4.6 mg/kg. This
cat was fifteen years old.
Plumb's Veterinary Drug Handbook (7th Ed.) states "Patients with severe
renal or hepatic impairment may require dosage adjustments to prevent
drug accumulation."
Urinary tract infection: how to diagnose and treat
correctly (2003) Brovida C
Presentation to the
World Small Animal Veterinary Association World Congress outlines how to modify the dosage of enrofloxacin for cats with kidney
disease.
Enrofloxacin may be given once daily or twice daily according to Plumb's
Veterinary Drug Handbook. However,
the manufacturer
states "once daily application of the total dose of
fluoroquinolones will have greater therapeutic effect compared to
treatment regimens where the dose is divided into two applications."
Therefore I would opt to dose once daily.
The manufacturer also states that
research in dogs indicates that enrofloxacin is most effective when given
one hour before food, preferably wet food. Plumb's Veterinary Drug
Handbook (7th Ed.) states "This drug is best given on an empty stomach
without food, but if your animal vomits or acts sick after getting it,
give with food or small treat (no dairy products, antacids or anything
containing iron) to see if this helps."
The recommended maximum course of treatment is 30 days (although Harpsie
was on a longer course a couple of times for his kidney infections with no problems).
Enrofloxacin Side Effects
Possible side effects
include nausea, vomiting or diarrhoea, though from what I have seen over
the years, these side effects seem to occur far less commonly than they do with amoxicillin. Plumb's Veterinary Drug Handbook (7th Ed.) says
"enrofloxacin appears to carry a low risk of causing antibiotic-associated
diarrhea."
The main
concern with enrofloxacin is that in certain rare cases it has caused
retinal problems, including blindness, when given to cats in high doses.
Plumb's Veterinary Drug Handbook (7th Ed.) says "Use of the canine or
bovine injectable products in cats is controversial and may result in
significant adverse effects. Parenteral administration in cats at doses
less than 5 mg/kg have reportedly caused ophthalmic toxicity (blindness)."
UK National Office of Animal Health states "In
target animal studies, cats have been shown to suffer ocular damage after
receiving doses of more than 15 mg/kg once daily for 21 consecutive days.
Doses of 30 mg/kg given once daily for 21 consecutive days have been shown
to cause irreversible ocular damage. At 50 mg/kg given once daily for 21
consecutive days, blindness can occur."
The blindness
has reversed in some cases once enrofloxacin is stopped, but not in all.
The manufacturer
states that this class of antibiotics is not considered to be
harmful to the kidneys, and that tests on dogs indicated no evidence of
kidney damage even at high dosing levels. However,
ISFM consensus guidelines on the diagnosis and
management of feline chronic kidney disease(2016)
Sparkes AH, Caney S, Chalhoub S, Elliott J, Finch N, Gajanayake I,
Langston C, Lefebvre H, White J & Quimby J Journal of Feline Medicine &
Surgery18 pp219-239 state
"Avoid enrofloxacin in cats with CKD due to increased risk of
retinopathy at standard therapeutic doses.”
Small Animal Clinical Pharmacology (2nd
Ed.) (2008) Maddison JE, Page SW & Church DB Saunders Ltd says
“It has been postulated that the relatively open blood-brain barrier of
cats combined with the lipophilic properties of enrofloxacin predispose
cats to accumulating high concentrations of the drug in the CNS. The
risk may be higher in cats with urinary tract infections and concomitant
renal failure and care should be taken with dosage in geriatric cats or
those with liver or renal impairment.”
Enrofloxacin may lower the seizure threshold, so may not be the best choice in
cats with a tendency to have seizures. Although Harpsie had epilepsy,
fortunately for us he never had any problems with enrofloxacin.
Plumb's Veterinary Drug Handbook (7th Ed.) says "Injectable enrofloxacin
must not be mixed with, or come into contact with any IV solution
containing magnesium (e.g., Normosol-R, Plasmalyte-R, -A, or –56);
morbidity and mortality secondary to micro-precipitants lodging in
patients’ lungs have been reported."
Enrofloxacin Interactions
Enrofloxacin must not be given orally within two hours of products containing calcium, aluminium or
lanthanum (such as phosphorus binders)
or iron (such as Pet
Tinic), because they may inhibit absorption of the enrofloxacin.
Sucralfate must also be
give separately from enrofloxacin for the same reason.
Drugs has some information about this.
Enrofloxacin
Research
Antibiotics and kidney disease in cats is
a study at the University of California at Davis into enrofloxacin, which
is aiming to ascertain whether there is decreased excretion of injectable
enrofloxacin in cats with CKD.
Marbofloxacin
(Marbocyl, Zeniquin or Marboquin)
Marbofloxacin belongs to the fluoroquinolone family of antibiotics, the
same family as enrofloxacin (Baytril) and pradofloxacin (Veraflox). Trade names include Zeniquin and
Marbocyl.
Pet Place has some information about
marbofloxacin.
states "At
the therapeutic recommended dosage, no severe side-effects are to be
expected in dogs and cats."
Marbofloxacin may lower the seizure threshold, so may not be the best
choice in cats with a tendency to have seizures.
There is some
debate as to whether marbofloxacin can also cause blindness, as
occasionally has happened with enrofloxacin. Plumb's Veterinary Drug
Handbook (7th Ed.) says that as at July 2007 the FDA Adverse Drug Reaction
database had received 14 reports of blindness associated with
marbofloxacin.
Baytril says "Orbifloxacin and marbofloxacin, other fluoroquinolones approved for use in
dogs and cats, have also been reported to cause retinal damage and/or
blindness in cats. Results of these studies lead to the conclusion that
most veterinary approved fluoroquinolones show variable affinity for
retinal tissues in cats."
Marbofloxacin Interactions
Marbofloxacin must not be given orally within two hours of products containing calcium, aluminium or
lanthanum (such as phosphorus binders)
or iron (such as Pet
Tinic), because they may inhibit absorption of the marbofloxacin.
Sucralfate must also be
give separately from marbofloxacin for the same reason.
Pradofloxacin (Veraflox)
Pradofloxacin, trade name
Veraflox, is a third generation
antibiotic in the
fluoroquinolone family of antibiotics, the same family as enrofloxacin
(Baytril) and marbofloxacin (Zeniquin).
According to
The European Medicines Agency, initially
pradofloxacin was refused approval in the EU in 2006 because "the company
had not been able to identify a dose that was effective whilst at
the same time providing an adequate margin of safety. For this reason the
Committee concluded that the safety of pradofloxacin had not been
conclusively proven."
Things change, and pradofloxacin is approved for the treatment of respiratory and skin
infections in cats in both the EU and the USA. It is not approved for the treatment of urinary tract
infections in cats (it is in dogs), but Bacterial urinary tract infections
(2016) Dowling PM Merck
Veterinary Manual says "Pradofloxacin is only approved for skin
infections in cats in North America, but it is approved for treatment of
UTI in dogs in Europe and is used to treat feline UTI."
Bacterial urinary tract infections
(2016) Dowling PM Merck
Veterinary Manual does say, however, "fluoroquinolones should be
reserved for UTIs that involve gram-negative bacteria, especially
Pseudomonas, and for UTIs in intact male dogs and cats because of their
excellent penetration into the prostate gland and activity in abscesses."
One major
advantage of pradofloxacin is that, unlike enrofloxacin and marbofloxacin,
it does not appear to cause blindness.
Baytril says "In the development phase of pradofloxacin (Veraflox),
a specific study was designed to investigate the effects of this molecule
on the feline retina. This study clearly demonstrated retinal and
ocular safety of pradofloxacin in the cat at doses up to 50 mg/kg, i.e. an
at least tenfold safety margin."
Pradofloxacin is usually given once a day. Bacterial urinary tract infections
(2016) Dowling PM Merck
Veterinary Manual says "They are concentration-dependent killers with
a long postadministration effect, so once daily, high-dose therapy for a
relatively short duration of treatment is effective."
The usual dose is 3mg per kg of body weight. A 10lb (4.5kg) cat should
therefore receive 13.5mg.
The manufacturer used to recommends the following:
Cat Weight (kg)
Number of 15mg Tablets
Total Dose Given (mg per kg)
3.4 - 5.0
1
3.0 - 4.4
5.0 - 7.5
1.5
3.0 - 4.5
7.5 - 10.0
2
3.0 - 4.0
Veraflox UK
now simply says to give one 15mg tablet to a cat weighing 3.5-5.5kg.
Oral Suspension
The usual dose used to be 5mg per kg of body weight.
The manufacturer
now states "The dose of Veraflox is 3.4 mg/lb. (7.5 mg/kg) body
weight once daily for seven consecutive days. Use the syringe provided to
ensure accuracy of dosing to the nearest 0.1 mL"
Pradofloxacin
Side Effects
Pradofloxacin can lower the seizure threshold, so I would avoid using it
in cats prone to seizures.
Pet Place mentions that "Administration
can cause reversible drops in white blood cell counts. Drug should be
discontinued if there is any unexplained drop in leukocyte, neutrophil
and/or lymphocyte counts."
Pradofloxacin Interactions
Pradofloxacin must not be given orally within two hours of products
containing calcium, aluminium or lanthanum (such as phosphorus binders)
or iron (such as Pet
Tinic), because they may inhibit absorption of the pradofloxacin.
Sucralfate must also be
give separately from pradofloxacin for the same reason.
Mar Vista Vet states "If pradofloxacin is used with oral cyclosporine
(an immunosuppressive medication used for inflammatory bowel disease),
the kidney damaging properties of cyclosporine may become worse."
Clindamycin
(Antirobe)
Clindamycin
belongs to the lincosamide family of antibiotics. One trade name is
Antirobe.
Clindamycin is approved for
treating skin and dental infections in cats. It is often prescribed for
dental problems because it is particularly good at killing anaerobic
bacteria which are commonly found in the mouth. I have used it for this
purpose in my own cats, and it is the antibiotic I would choose for this
purpose.
Clindamycin
should be used with caution in CKD cats - the normal dosage may need to be
adjusted.
Mar Vista Vet
states "The manufacturer has
recommended blood tests of liver and kidney function if use of clindamycin
is to persist beyond 30 days."
Clindamycin Formulations
Clindamycin is available in 25mg and 75mg capsules (which in theory
are for dogs only). It is also
available as a liquid medication in a 25mg/ml strength.
Clindamycin Dosage
The manufacturer
recommends a dose for cats of 5-15 mg per pound (11-33mg per kg) once a
day for a maximum of fourteen days.
Always give
with food or follow with water to avoid damaging the oesophagus.
Clindamycin Side Effects
Clindamycin is
notorious for tasting awful, so it may be better to give it in a gelcap.
Like most
antibiotics, clindamycin may cause diarrhoea, vomiting and drooling.
Clindamycin (2015)
Clarke M Plumb's Therapeutic Brief May 2015 says "Administer
with caution in patients with very severe renal disease and/or hepatic
disease accompanied by severe metabolic aberrations."
Cefpodoxime (Simplicef)
Cefpodoxime is
an antibiotic in the cephalosporin class of antibiotics, the same family
as cefovecin (Convenia).
Cefpodoxime is commonly used to treat skin infections and urinary tract
infections.
Cefpodoxime Formulations
Cefpodoxime is available in 100mg and 200mg capsules.
It is also available as a liquid medication in 50 mg/5ml and 100
mg/5ml strengths.
Cefpodoxime Dosage
A typical dose is 10 mg per kg (5mg per pound) of cat, given once a
day, or 5 mg per kg (2.5 per pound) of cat, given twice a day. It can
be given with or without food.
Drugs says "Dosage adjustments may be
necessary and modifications should be based on the degree of renal
impairment as well as severity of infection in accordance with the
individual product package labeling."
Cefpodoxime Side Effects
As with many antibiotics, loss of appetite, vomiting, lethargy and
diarrhoea may be seen. Vomiting is the most common side effect with
cefpodoxime.
Drugs says "Renal function tests
should be performed periodically during prolonged and/or high-dose
therapy, since nephrotoxicity and alterations in renal function have
occasionally been associated with the use of these drugs."
Cefovecin is a third generation antibiotic in the cephalosporin class
of antibiotics, the same family as cefpodoxime (Simplicef). The brand name is Convenia.
Cefovecin under the brand name of Convenia
was approved as follows:
in Europe in 2006 for the treatment of skin infections and urinary
tract infections in cats and dogs.
in the USA in 2008 for the treatment of skin infections in dogs and
cats, and urinary tract infections in dogs only.
The European Medicines Agency
states "It is prudent to reserve third generation cephalosporins for
the treatment of clinical conditions, which have responded poorly, or
are expected to respond poorly, to other classes of antimicrobials or
first generation cephalosporins."
Pet Place mentions that "Maximum
treatment should not exceed 2 injections."
Other sources state that it may be
used up to three times.
However,
the manufacturer has stated (2013)
that Convenia "should be administered as a single, one-time
subcutaneous injection at a dose of 3.6 mg/lb (8 mg/kg) body weight."
If you do give it more than once, it should not be given more frequently than once every two
weeks.
Cefovecin Side Effects
Possible side effects include lethargy, vomiting and diarrhoea. There
may also be skin irritation at the injection site.
Other, more worrying possible side effects include
haemolytic anaemia or
pulmonary oedema, though fortunately these are rare.
Drugs reports on possible side
effects.
Cefovecin has not been tested in cats with severe kidney problems, but
Drugs reports that some cats in a
safety study had mild elevations in BUN and creatinine levels after
they were given it.
There are a number of websites claiming that cefovecin is very dangerous
for cats, and certainly some cats have had problems which might have
been caused by the medication. Plumb's Veterinary Drug Handbook 7th
Ed. states "Hypersensitivity reactions, anaphylaxis and death
associated with this drug are possible and have been reported."
Center for Veterinary Medicine adverse drug
events report listing (2013) reports (page 294) on the
adverse effects reported to be associated with the use of cefovecin in
cats up until 1 March 2013, including 166 deaths and 148 cases of
anaemia. Whilst this is worrying, people never seem unduly concerned
that 66 deaths were also reported as being associated with amoxicillin
and clavulanate.
Cefovecin can remain in the body for up to 65 days.
If your cat does have a bad reaction, the fact that it is so
long lasting becomes a disadvantage, because your cat's body remains
exposed to the drug.
Many people I have heard from who have used cefovecin were pleased
with it. My Ollie was given this for a urinary tract infection and he
did not show any adverse reactions, but his UTI symptoms began to
return about 10 days after the shot, so we switched to amoxicillin and
clavulanate, which seemed to work better for him.
Cefovecin Interactions
Famotidine (Pepcid AC) can interfere with antibiotics in the
cephalosporin family such as cefovecin, so you should separate the two treatments by two hours.
I am sometimes asked why I mention this when cefovecin is an injectable
medication.
H2-antagonist cephalosporin interactions
(2003) Ali A Thesis states "These interaction studies with
H2-receptor antagonists in gastric as well as blood pH revealed that
simultaneous use of these drugs depressed the availability of the
antibiotic as well as cimetidine, ranitidine and famotidine."
Plumb's
Veterinary Drug Handbook does not mention cefovecin
specifically, but does mention that taking other members of the
cephalosporin family with food may offset the reduced absorption of
the antibiotic.
Metronidazole (Flagyl)
Metronidazole is an anaerobic antibiotic which is not
commonly used in CKD cats, but it is anti-inflammatory in the digestive
tract, so it can be very helpful for diarrhoea. Therefore it is often used
in cats with colitis or IBD. It is occasionally used for dental problems,
since oral bacteria are often anaerobic. Because of its anti-inflammatory
effects, it is also sometimes used in cats with
pancreatitis.
Metronidazole is known for its horrible taste.
Neurological problems can occasionally be seen, though
these are rare and usually associated with either long term use (over a
period of months) or high doses. The neurological problems usually resolve
within a couple of weeks of stopping the medication.
Pet Place discusses metronidazole
toxicity but mentions it is uncommon and usually associated with long term
use.
CKD is not usually a painful disease, so painkillers are not normally part
of a CKD treatment plan. However, CKD cats may sometimes
require painkillers for other reasons, so here is some information about the various painkillers that
may be used in cats.
It is easier to stop pain developing rather than trying to control it once
it has begun, so if for example your cat is about to have a dental, be
sure to discuss pain control with your vet in advance.
If your cat is in pain, you must treat it.
Pain Assessment
Unfortunately it can be difficult to know when a cat is in pain. This is
because firstly, cats instinctively try to hide the
fact that they are in pain; and secondly, some of the signs of pain in cats are
different to what you might expect, e.g. purring,
restlessness. Other possible signs include growling, avoiding
interactions, sleeping a lot or sitting in a hunched position.
Please see the
Symptoms
chapter for more information on the signs of pain in cats.
We cannot always know that our patient does hurt, but
we can do our best to ensure that it does not hurt."
Painkillers Choices
Many painkillers which work well for dogs and humans are not tested on
cats and therefore not approved for use in cats. Therefore most of the
products discussed below are used off-label in cats.
It is wise to consider the use of additional treatments, such as
nutraceuticals and/or acupuncture for arthritic cats and anti-nausea medications for cats
with pancreatitis. This may enable you to lower the dose of the painkillers
you are using.
WSAVA guidelines for recognition, assessment and
treatment of pain (2014) Mathews K, Kronen PW, Lascelles D,
Nolan A, Robertson S, Steagall PVM, Wright B & Yamashita K Journal of
Small Animal Practice55(6) ppE10–E68
say "The authors recommend that
particularly in all chronic pain patients, non-drug treatment modalities
should be used alongside pharmaceutical treatments."
2015 AAHA/AAFP pain management guidelines for dogs
and cats (2015) Epstein ME, Rodan I, Griffenhagen G, Kadrlik J,
Petty MC, Robertson SA & Simpson W Journal of Feline Medicine and
Surgery17 pp251–272
has a helpful overview of the various painkillers
available.
Opiates are narcotics, which means they belong to the same drug family as
morphine. These drugs are derived from the poppy and are the most
powerful painkillers.
2015 AAHA/AAFP pain management guidelines for dogs
and cats (2015) Epstein ME, Rodan I, Griffenhagen G, Kadrlik J,
Petty MC, Robertson SA & Simpson W Journal of Feline Medicine and
Surgery17 pp251–272 say
"opioids are the most effective drug
class for managing acute pain and can play a role in managing chronic pain."
Opioid therapy (2011) Thompson D
Veterinary Anesthesia and Analgesia Support Group has an overview of opiates.
Buprenorphine (Buprenex, Vetergesic,
Temgesic)
Buprenorphine, sometimes colloquially referred to as bupe, is a narcotic
which is thirty times more potent than morphine. Trade names include
Buprenex (USA), Vetergesic (UK) and Temgesic (UK and Australasia).
Because it is such a powerful opioid, buprenorphine is a controlled
substance in most countries.
Buprenorphine is a popular choice for cats because it works promptly and
effectively, lasts for 6-8 hours (longer in some formulations), and has
relatively few side effects.
Buprenorphine is available in an injectable form which, rather
confusingly, may be
administered intravenously, intramuscularly, subcutaneously or transmucosally.
The intravenous and intramuscular methods of administration are normally
only used in a clinic setting.
For home use, your options are therefore transmucosal application (oral)
or subcutaneous injection.
Buprenorphine: Transmucosal
(OTM or Intrabuccal)
Buprenorphine should not be given orally (as in, swallowed) because it is
ineffective when given in such a way.
However, it is often given in transmucosal (intrabuccal) form, i.e. it is placed in the mouth
(usually by being squirted from a syringe) between the cheek and the gum. When
applied to the mucus membranes in this way, it can be
easily and quickly absorbed by the body, within around 30 minutes, with its effects
lasting for around eight hours.
Systemic update of buprenorphine by cats after oral
mucosal administration (2003) Robertson SA, Taylor PM & Sear JW
Veterinary Record152(22) pp675-8 found that administering
buprenorphine via the oral mucosal route was as effective as injecting it,
and the majority of owners preferred this method of administration.
A review of the studies using buprenorphine in cats
(2014)
Steagall PVM, Monteiro-Steagall BP & Taylor PM Journal of Veterinary
Internal Medicine28 pp762-70 says "At clinical dosages... the
buccal route has produced inconsistent results." However,
WSAVA guidelines for recognition, assessment and
treatment of pain (2014) Mathews K, Kronen PW, Lascelles D,
Nolan A, Robertson S, Steagall PVM, Wright B & Yamashita K Journal of
Small Animal Practice55(6) ppE10–E68
say "buprenorphine given by the
oral transmucosal route has been demonstrated to produce effective
antinociception [pain blocking] in cats", and
2015 AAHA/AAFP pain management guidelines for dogs
and cats (2015) Epstein ME, Rodan I, Griffenhagen G, Kadrlik J,
Petty MC, Robertson SA & Simpson W Journal of Feline Medicine and
Surgery17 pp251–272 say
"The oral transmucosal or buccal route of administration for
buprenorphine may have clinical efficacy as well." Certainly many members of
Tanya's CKD Support Group find it seems to work well for their cats.
The buprenorphine used for this purpose is the standard (not the extended
release versions) injectable form of buprenorphine.
It is flavourless so most cats tolerate this well.
Buprenorphine Subcutaneous
Subcutaneous buprenorphine has long been considered to be ineffective at
standard (0.02mg/kg) doses.
A review of the studies using buprenorphine in cats
(2014)
Steagall PVM, Monteiro-Steagall BP & Taylor PM Journal of Veterinary
Internal Medicine28 pp762-70 says "At clinical dosages,
the SC route of administration does not appear to provide adequate
antinociception and analgesia."
2015 AAHA/AAFP pain management guidelines for dogs
and cats (2015) Epstein ME, Rodan I, Griffenhagen G, Kadrlik J,
Petty MC, Robertson SA & Simpson W Journal of Feline Medicine and
Surgery17 pp251–272 say "in cats, the
subcutaneous (SC) route of opioid administration is not recommended."
Increasing the doses would not necessarily make buprenorphine work more
effectively, because it is known for having a "ceiling effect."
Mar Vista Vet
explains "While buprenorphine is commonly dispensed for three times
daily usage, how long a dose lasts actually depends on the size of the
dose. This is possible because of buprenorphine's "ceiling effect" which
means that once a maximum effect has been reached (i.e. all the receptors
have been bound with drug), giving more buprenorphine does not create a
greater effect. Instead, the higher the dose, the longer the effects
last."
Recent research indicates that giving
more concentrated doses subcutaneously may actually provide effective pain
relief for longer periods without adverse effects.
Pharmacokinetic and pharmacodynamic evaluation of
high doses of buprenorphine delivered via high-concentration formulations
in cats (2016) Taylor PM, Luangdilok CH & Sear JW Journal of Feline
Medicine and Surgery 18(4) pp290-302 looked at the
effectiveness of buprenorphine given subcutaneously to healthy cats. The study found that higher doses lasted for over 24 hours, sometimes close to 48
hours. The study concludes "0.12 and 0.24 mg/kg doses of aqueous
buprenorphine given subcutaneously appear to provide at least 24 h
antinociception with no side effects other than mydriasis [dilated
pupils]."
Newer formulations have been released as follows:
Simbadol
Simbadol is a form of buprenorphine which
is given by subcutaneous injection and which is said to last for 24 hours,
so it only needs to be given once a day.
Drugs
mentions that two cats died during trials of Simbadol because of apnoea
(stopping breathing). The trials involved 450 cats, all of whom underwent
surgery. One of the cats had undiagnosed cancer, the other had no obvious
health problems. Most CKD cats receive buprenorphine while conscious
rather than during surgery.
Buprenorphine SR
Buprenorphine SR is a sustained release form
of buprenorphine which is given by subcutaneous injection and which is
supposed to last for 72 hours.
Buprenorphine Dosage
The doses given below are commonly used in cats. However,
A review of the studies using buprenorphine in cats
(2014)
Steagall PVM, Monteiro-Steagall BP & Taylor PM Journal of Veterinary
Internal Medicine28 pp762-70 says "Cats may have great individual variability with respect to the number,
morphology, and distribution of opioid receptors relative to other
species..., so buprenorphine may not provide sufficient analgesia in some
cats, and it may be very effective in others. Analgesic protocols should
be tailored to the individual patient."
Transmucosal
The usual dose is 0.01-0.03 mg/kg, which is given up to three times a day.
Here is a table showing what this means for cats of different weights:
Cat Weight
Dosage
in mg
0.01 mg/kg dose
0.02 mg/kg dose
0.03 mg/kg dose
5 lb (2.27kg)
0.0227
0.0454
0.068
8 lb (3.64kg)
0.0364
0.0728
0.109
10 lb (4.5kg)
0.0450
0.0901
0.135
Injectable buprenorphine (which is what you will probably be using,
but applying to the cheek) is available in a number of different strengths.
Since these are tricky amounts to calculate, many vets provide small
syringes containing the correct dose and you just gently squeeze the
contents into your cat's mouth towards the cheek.
Subcutaneous
The usual dosage of Simbadol (1.8 mg/mL) is 0.24 mg/kg (0.11 mg/lb) administered
subcutaneously once daily, for up to 3 days.
Buprenorphine Sources
Buprenorphine is available in vials (not usually offered to clients in the
USA) or
small prefilled syringes, each containing about 1ml of buprenorphine.
These contain injectable buprenorphine, but it is safe to give this
by squirting the contents of the syringe into the cheek as long as it is not the sustained release version.
Since the introduction of sustained release buprenorphine, some vets are
no longer supplying syringes to clients for home use (since buprenorphine
is a controlled drug), and instead are only prepared to administer the subcutaneous
sustained release injectable version in their office. This would require
two trips to the vet each week, which is not ideal for most people or
cats.
Some people prefer to obtain oral suspension buprenorphine instead.
This compounding pharmacy is used by many members of Tanya's CKD Support
Group for buprenorphine. It offers an oral suspension made
from a powder mixed with preserved water which you
can then apply to your cat's cheek inside the mouth.
The strength dispensed is typically 0.3mg/ml. It will dispense the product
as directed by your vet, but the price is the same for any amount up to 30
mls, which is good for up to 180 days.
The price as at January 2019 was US$40 for a bottle up to 30 ml in size
plus US$8 flat rate shipping.
You will also need syringes to draw up and give the medication.
Diamondback also compound an injectable form in an 0.6 mg/ml strength which comes
in a 10 ml vial, but this is probably too high a strength for most cats,
plus it contains a preservative which may sting.
This compounding pharmacy charges around US$50 (June 2020) for 15ml of a
0.3mg/ml strength product. The link is for 0.6mg/ml strength, but I
understand they will do the lower strength upon request.
UK
In the UK you will often be offered buprenorphine for home use in 5ml or
1ml vials.
Although the 5ml and 10ml vials tend to be cheaper, it is better to buy the 1ml
vials because there is a preservative added to the larger size vials which gives
the medication an unpleasant taste.
Buprecare is one possible brand, which is
available in a 0.3mg/ml strength. This product does not contain a
preservative.
Buprenorphine makes some cats purr more and become very affectionate, whilst other
cats become restless.
The main concern is respiratory depression, which may be seen as slowed
breathing and/or shallower breathing. However, Plumb's Veterinary Drugs
Handbook (7th Ed.) says this is rare, though it advises that buprenorphine "should
be used cautiously in patients with compromised cardiopulmonary function."
Buprenorphine is cleared by the liver so it tends to be a good choice for
CKD cats who need ongoing pain control. However, cats with CKD may
eliminate it more slowly. Plumb's Veterinary Drugs Handbook says "All
opiates should be used with caution in patients with... severe renal
insufficiency... and in geriatric or severely debilitated patients."
Discuss with your vet whether to lower the dose.
Virtually everybody I've heard from has found buprenorphine
extremely effective with few side effects.
Buprenorphine
Interactions
Be careful if you are using buprenorphine with
cyproheptadine
(an appetite stimulant) because using both together may result in an
increased sedative effect.
Drugs
mentions that the risk of respiratory depression is increased if
buprenorphine is used concomitantly with
gabapentin.
Fentanyl (Duragesic)
Fentanyl is a narcotic belonging to the same drug family (opioids) as
buprenorphine and morphine.
Therefore it is a very effective painkiller.
Fentanyl is usually given in the form of a patch (like a plaster) on the
skin which slowly releases the medication for 4-5 days.
My Indie (non-CKD) had
extensive dental extractions, and was given a fentanyl patch
to help her oral pain. The patch was applied to a small area of shaved
skin on one of her back legs, and lasted for several days. It worked very
well for her, she was a little subdued but that was the only side effect
(which might actually have been due to the after effects of the surgery).
However, up to a third of cats absorb less of the medication than is
needed for effective pain control, so be aware of the
signs of pain in cats so
you can ensure it is working properly for your cat.
Fentanyl Side Effects
Side effects are uncommon and usually minor e.g. allergy to the patch
adhesive.
The most common serious side effect (although it is still relatively rare)
is an adverse effect on breathing, which may manifest itself as lethargy.
Fortunately removing the patch should quickly resolve any problems.
Care should be taken to ensure that the cat cannot remove the patch or
lick it.
Fentanyl Interactions
Fentanyl should not be used in cats taking selegiline (Anipryl) for
cognitive
dysfunction.
Heat can increase the amount of fentanyl released, which could be very
dangerous, so access to heat (e.g. heated cat beds) should be removed for
any cat with a fentanyl patch.
Tramadol (Ultram)
Strictly speaking tramadol is not an opiate but it has some effect on
opioid receptors, so I am including it in this category.
Pain medicine: Tramadol
Moses L Angell Animal Medical Center explains that response
to tramadol varies from patient to patient, and that it may be better to
use it in conjunction with other pain control methods. Fortunately it can
be used safely in conjunction with a number of other medications.
Mar Vista Vet says "The
beauty of tramadol as a pain reliever is that it is compatible with all
the COX-inhibiting non-steroidal anti-inflammatory drugs, possibly even
synergizing with them. The same is true with tramadol combined with
gabapentin and amantidine. It is also compatible with joint pain
nutriceuticals such as glucosamine, MSM, chondroitin sulfate etc."
mentions that if tramadol is used longer term, it
should be tapered off rather than stopped suddenly.
Tramadol Side Effects
Tramadol is a safe treatment when used at appropriate dosage levels and
side effects are rare, but include sedation, loss of appetite, vomiting and constipation.
Dilated pupils may also be seen in cats.
Tramadol has been known to cause hallucinations and seizures in humans so
should be used with caution in cats with a history of seizures.
Be careful if you are using tramadol at the same time as
cyproheptadine
(an appetite stimulant) because using both together may reduce the effectiveness
of the tramadol.
Mar Vista Vet
mentions that using
tramadol at the same time as another appetite stimulant called
mirtazapine may increase the risk of serotonin syndrome.
Non-Steroidal
Anti-Inflammatory Drugs (NSAIDs)
Non-steroidal anti-inflammatory drugs help to reduce inflammation and may
offer some degree of pain control.
ISFM and AAFP consensus guidelines: long-term use of
NSAIDs in cats (2010) Sparkes AH,
Heiene R, Lascelles BDX, Malik R, Real Sampietro L, Robertson S, Scherk M
& Taylor P Journal
of Feline Medicine and Surgery 12 pp521-538 provide
guidelines for their use. The guidelines are also available in
French, German, Japanese and Spanish
here.
NSAIDs work by blocking prostaglandin production. They do this by binding
with enzymes called cyclo-oxygenase (CoX).
There are two forms of CoX:
CoX-1 is protective, particularly in the kidneys and the digestive tract.
CoX-2 produces pain and inflammation.
Therefore the goal is usually to reduce levels of CoX-2 whilst not affecting CoX-1.
Reducing levels of CoX-2 only does not entirely remove the
risk of side effects.
2015 AAHA/AAFP pain management guidelines for dogs
and cats (2015) Epstein ME, Rodan I, Griffenhagen G, Kadrlik J,
Petty MC, Robertson SA & Simpson W Journal of Feline Medicine and
Surgery17 pp251–272
say "Studies indicate that NSAiDs that spare
cyclooxygenase (CoX)-1 produce a lower frequency of Gi lesions." However,
the guidelines also say "the more highly CoX-2selective inhibitors may actually produce more
adverse events when underlying gastric damage is already present."
Most NSAIDs used in cats are relatively cheap and very effective. They are
usually supplied in formulations that are easy to give too.
Because they are anti-inflammatory, NSAIDs can be very helpful,
especially for chronic conditions such as arthritis.
2015 AAHA/AAFP pain management guidelines for dogs
and cats (2015) Epstein ME, Rodan I, Griffenhagen G, Kadrlik J,
Petty MC, Robertson SA & Simpson W Journal of Feline Medicine and
Surgery17 pp251–272
say "The majority of conditions that cause pain have an inflammatory
component. Non-steroidal anti-inflammatory drugs (NSAiDs) are a mainstay
for management of chronic pain as well as for perioperative use."
As regards safety, they also state "NSAiDs should be used for their
central and peripheral effects in both dogs and cats after consideration
of risk factors. There is no indication that any one of the
veterinary-approved NSAiDs is associated with any greater or lesser
incidence or prevalence of adverse events."
Unfortunately cats tend to metabolise NSAIDs poorly, so
historically many vets have been reluctant to use these medications in cats
because of the risk of side effects.
Pet Poison Helpline
explains more about the risks of using NSAIDs and what warning signs to
watch for.
2015 AAHA/AAFP pain management guidelines for dogs
and cats (2015) Epstein ME, Rodan I, Griffenhagen G, Kadrlik J,
Petty MC, Robertson SA & Simpson W Journal of Feline Medicine and
Surgery17 pp251–272 state "of the
adverse events associated with NSAiDs, gastrointestinal (Gi) toxicity is
the most common. In cats, inappetence appears to be the most common
adverse event." It also says "Although the overall incidence and
prevalence of NSAiD-related toxicity is unknown, it does appear to be very
low relative to the number of doses administered."
Research indicates that
NSAIDs are usually safe for short-term use in healthy cats when used
appropriately.
Effects of non-steroidal anti-inflammatory drugs
(NSAIDs) on renal function (2007)
Brown SA State of the Art in Renal Disease in Dogs and Cats
Proceedings, Vetoquinol Academia reports (page 31) on the use of
NSAIDs in CKD. Dr Brown states "It has long been known that NSAIDs have a
good margin of renal safety for short- term use in healthy animals."
See below for more information on the use of NSAIDs in cats with CKD.
NSAIDS should not be used at the same time as
corticosteroids.
Close monitoring is required if NSAIDs are used in cats taking
ACE
inhibitors such as benazepril or
diuretics
because using these treatments together increases the risk of kidney
problems.
Non-Steroidal Anti-Inflammatory Drugs (NSAIDs):
Use in CKD Cats
Some vets do not like using NSAIDs in CKD cats, while others feel they are
can be safely used in certain circumstances.
Many cats require NSAIDs longer-term, e.g. to treat arthritis.
Although some oral NSAIDS are approved for use longer-term in cats in some
countries, caution is still advised for cats with certain
problems such as CKD.
2015 AAHA/AAFP pain management guidelines for dogs
and cats (2015) Epstein ME, Rodan I, Griffenhagen G, Kadrlik J,
Petty MC, Robertson SA & Simpson W Journal of Feline Medicine and
Surgery17 pp251–272
say "Be cautious or avoid NSAIDs in patients
with the following existing/anticipated conditions:
– Low-flow states such as dehydration, hypovolemia, congestive heart
failure and hypotension.
for long-term NSAID administration." The paper says NSAIDs should only be
used in CKD cats:
who are stable, with few changes in weight or creatinine for at least two
months, and with other problems such as hypertension under control
ideally in IRIS stage 1 or 2, and possibly 3 in some circumstances
well hydrated
at the lowest effective dose
with phosphorus levels kept under control
with regular ongoing monitoring, including by the caregiver
in conjunction with other pain management techniques, such as acupuncture
The study concludes "based on current evidence, the WSAVA-GPC [World Small
Animal Veterinary Association-Global Pain Council] supports the long-term
administration of the lowest effective doses of meloxicam and robenacoxib
in cats with concomitant chronic pain and CKD as part of a multimodal
approach that includes non-pharmacological therapies, unless
contraindicated."
Meloxicam is a non-steroidal anti-inflammatory drug
that may be used in cats for acute or chronic pain.
Meloxicam is a CoX-2 preferential NSAID, i.e. it
works effectively on CoX-2 to reduce pain and inflammation, but it also
reduces levels of CoX-1 to some degree. See
above
for more about this.
Meloxicam is available
in both injectable and oral (liquid) form, as
follows:
USA
Only approved (under the trade name of
Metacam) for use in cats in the
injectable form.
Intended to be a one-off treatment as a painkilling injection following
surgery.
A canine oral version is available which is sometimes used off-label in
cats.
Europe
The injectable form is approved for
one-off use in cats following surgery, the same as in
the USA.
An oral form was licensed in 2007 for use in cats for
longer term pain management e.g. in cats with arthritis, under the trade name
of Metacam.
Another oral form was licensed in 2011 for use in cats
for longer term pain management e.g. in cats with arthritis, under the trade name
of Meloxidyl.
Meloxicam
Risks and Benefits
Many people are frightened to use meloxicam in their cats, particularly in
cats with CKD. This is largely because a
Freedom of Information Summary(2004) US Food and Drug Administration stated
(page 23) that, following the use of Metacam for post-operative pain, 8.3%
of the cats in the study had elevated
BUN
levels, and 12.5% had
anaemia (anaemia is common in cases of
inflammation, which may partly explain this finding, since meloxicam is an
anti-inflammatory medication). The paper
concludes: "Meloxicam, when initially dosed as a subcutaneous injection
followed by oral dosing for nine days at > 0.3 mg/kg was associated
with severe adverse effects, including death."
This was followed in October 2010 by the Food and Drug Administration
announcing
that a
"black box warning" would be added to meloxicam.
The black box warning
states: "Warning. Repeated use of meloxicam in cats has been
associated with acute renal failure and death. Do not administer
additional injectable or oral meloxicam to cats. See contraindications,
warnings and precautions for detailed information."
Other countries take a different view of meloxicam, as shown by their
approval of oral versions of meloxicam for longer term use in cats. In
fact, research since the black box warning was issued in 2010 indicates
that meloxicam can be safe for healthy cats, and even for CKD cats as long
as safety guidelines are followed.
Subsequent studies looked at the longer term use of meloxicam.
Long-term safety, efficacy and palatability of oral
meloxicam at 0.01-0.03mg/kg for treatment of osteoarthritic pain in cats
(2008) Gunew MN, Menrath VH, Marshall RD
Journal of Feline Medicine & Surgery
10(3) pp235-41
monitored forty cats who were given meloxicam for arthritis for almost six
months, three of whom had pre-existing renal disease. The study found that
"no deleterious effect on renalfunction
was detected in cats studied."
Retrospective case-control study of the effects of long-term dosing with
meloxicam on renal function in aged cats with degenerative joint disease
(2011) Gowan RA, Lingard AE, Johnston L, Stansen W, Brown SA, Malik
R
Journal of Feline Medicine & Surgery13(10) pp752-761
retrospectively examined the records of a veterinary practice over a five
year period and concluded that "long-term therapy with meloxicam at a
median dose of 0.02 mg/kg/day can be administered safely to aged cats with
CKD, provided they are clinically stable. The results further suggest that
meloxicam may actually slow the progression of renal disease in cats with
both DJD and CKD by direct or indirect mechanisms." The study goes
on to speculate that meloxicam might slow the progression of CKD by
reducing proteinuria (studies indicate that medications in the same
family as meloxicam can reduce proteinuria in humans and rats).
A retrospective analysis of the effects of meloxicam
on the longevity of aged cats with and without overt chronic kidney
disease (2012) Gowan RA, Baral RM,
Lingard AE, Catt MJ, Stansen W, Johnston L & Malik R
Journal of Feline Medicine and Surgery14(12) pp876-81
looked into the use of meloxicam in cats with CKD. This study examined the
records of 82 cats over the age of seven who had been given meloxicam for
six months or longer. 47 of the cats were known to have CKD, the other 35
showed no obvious signs of CKD. The most common cause of death in both
groups was cancer, not CKD. The study concluded "the survival data
presented here confirm that many cats with carefully managed CKD can
survive for a substantial period with standard medical therapy. In
addition, long-term treatment with oral meloxicam did not appear to reduce
the lifespan of cats with pre-existent stable CKD, even for cats in IRIS
stages II and III."
Meloxicam can be very helpful for cats with arthritis. There is more
information about using it in cats with arthritis
here.
Meloxicam Dosing
The dosage used appears to be critical when it comes to
benefiting from meloxicam whilst reducing the risk of any problems.
It is also
important not to use oral meloxicam after injectable meloxicam. I know
many vets do offer oral meloxicam following the use of injectable
meloxicam during surgery such as spaying, but it should be noted that
the manufacturer says "Metacam 0.5 mg/mL Oral Suspension for Cats should
not be used following parenteral injection of meloxicam or any other NSAID
as appropriate dosage regimens for such follow-up treatments have not been
established."
Meloxicam Dosing: Healthy
Cats
For healthy cats, the dose of the oral medication recommended by
one manufacturer for the
treatment of chronic pain in cats is:
a single oral dose of 0.1 mg meloxicam/kg body weight on the first day.
a maintenance dose of 0.05 mg meloxicam/kg body weight once daily
thereafter at 24 hour intervals.
"For longer term treatment, once clinical response
has been observed (within 7 days), the dose of Metacam can be adjusted
to the lowest effective individual dose reflecting that the degree of
pain and inflammation associated with chronic musculoskeletal disorders
may vary over time."
Adverse reactions to meloxicam have been reported much more
frequently in the USA than in countries where oral meloxicam is
approved for longer term use in cats. This may be because those countries
provide vets with guidelines on suitable doses for cats, which is not the
case in the USA.
The fact that the USA has not approved a feline
formulation may actually be contributing to the problem, because vets in
the USA who wish to prescribe meloxicam off-label for a feline patient
have to prescribe the canine version, which is three times as strong as
the feline version available in other countries. Vets should
of course be reducing the dose for their feline patients, but
since meloxicam is often dosed in drops rather than precise measurements,
it may be that they are instructing their clients to give it in drops (Metacam comes with a dropper
dispenser) directly into the cat's mouth rather than measuring it out in
mg first, and thus not adjusting the dose appropriately and safely for cats.
If your cat develops kidney
problems following the use of meloxicam, please see
below for information on how best to treat it, and how to report it to
the authorities.
Meloxicam Dosing: CKD Cats
If you wish to
use meloxicam in a CKD cat, one option is to give half of the
dose that you would give to a healthy cat of the same weight and see if it
helps your cat.
Retrospective case-control study of the effects of long-term dosing with
meloxicam on renal function in aged cats with degenerative joint disease
(2011) Gowan RA, Lingard AE, Johnston L, Stansen W, Brown SA, Malik
R
Journal of Feline Medicine & Surgery13(10) pp752-761
retrospectively examined the records of a veterinary practice over a five
year period and concluded that "long-term therapy with meloxicam at a
median dose of 0.02 mg/kg/day can be administered safely to aged cats with
CKD, provided they are clinically stable."
Please note the study refers to cats with stable CKD. If your cat
has recently crashed, or is dehydrated or is not eating, meloxicam is
unlikely to be suitable. The study also says "Adverse effects on the
kidney occur when NSAIDs are used in cats that are dehydrated,
hypovolaemic or hypotensive, but meloxicam is not of itself nephrotoxic,
and there is evidence that for cats with stable CKD and chronic pain, use
of low dose meloxicam can achieve improved survival and maintenance of
bodyweight with no acceleration of renal deterioration."
ISFM and AAFP consensus guidelines: long-term use of
NSAIDs in cats (2010) Sparkes AH,
Heiene R, Lascelles BDX, Malik R, Real Sampietro L, Robertson S, Scherk M
& Taylor P Journal
of Feline Medicine and Surgery 12 pp521-538
has a box on page 530 which explains the precautions that should be taken when using NSAIDs in cats with renal disease.
Meloxicam: Whether To Use
Some people
refuse to use meloxicam for any of their cats, healthy or otherwise,
preferring to rely on other medications, usually painkillers.
I do not
personally view meloxicam as a last resort treatment. Yes, there are other
treatments available for pain control in cats, but meloxicam is
anti-inflammatory, whereas most of the alternatives are simply
painkillers. Meloxicam is also easy to give, very effective and
reasonably priced.
I would
definitely consider using meloxicam for a cat whose kidneys appeared fine
in tests and who would benefit from it, such as my arthritic
Karma. In fact, I wish I had started Karma on it far sooner than I did.
Buying into the fear of using NSAIDs in cats, I did not start giving
non-CKD Karma
meloxicam until she was already sixteen years old and had had arthritis
for some years. I am still kicking myself for not giving it to her sooner,
because the difference was like night and day: she was just so much
happier and more active once her pain was under control.
We also used
meloxicam for Harpsie when his arthritis flared up acutely following a
fall off a sofa while we were out and he was in dreadful pain which other
medications did not seem to help (he was literally screaming). It worked
very well and caused no long term problems for him, but since Harpsie had
PKD, we only used it at a very low dose, and much less
frequently than normally recommended, and it still controlled the pain
effectively. We checked his kidney values a month later (they were fine).
If either of
them had had CKD, I would still have considered using it (at very carefully
dosed levels with regular monitoring), bearing in mind that controlling pain is more important
for quality of life than anything else. It may be better for me to keep my
cats around for as long as possible, but I am not convinced that it is
better for my
cats to live a longer but pain-filled life.
Meloxicam Interactions
Close monitoring is required if NSAIDs are used in cats taking
ACE
inhibitors (such as benazepril or enalapril) or
diuretics
because using these treatments together increases the risk of kidney
problems.
Most cats who develop kidney problems after using
meloxicam are suffering from
acute kidney
injury (AKI). Therefore their kidney values in blood tests may be
extremely high, with creatinine often in the high teens.
A treatment programme which includes 4-5 days of IV
fluid therapy (hospitalisation), followed by 4-6 weeks of sub-Q fluids at
home, is often recommended by the manufacturers, but talk to them (see
below) and see what they suggest for your cat.
I would also suggest that you ask the manufacturers to
pay your veterinary costs — I know they have done this for some people,
although they have not necessarily paid the full costs. It would appear
that they may pay more if your vet calls.
Do not give up hope! Acute kidney injury is
difficult to treat, but not impossible: an aggressive treatment plan
should see those numbers dramatically reduce in most cases, and in some
cases a complete recovery from a case of acute kidney injury is possible.
In fact, one person was told by the manufacturer of Metacam that 77% of cats affected
by meloxicam make a full recovery with prompt and proper treatment, so don't
opt for euthanasia immediately.
However, I understand that the manufacturer considers a
creatinine in the 3 mg/dl range to indicate that the cat is stabilised, and whilst
this is certainly not a critical level nor grounds for euthanasia, it does
indicate some residual kidney damage.
Meloxicam: Reporting
Adverse Reactions
If you believe your cat has developed kidney disease as
a result of using meloxicam, you should report this as follows:
USA
If you have used Metacam, contact the manufacturer on
1-866-METACAM (638-2226). You may find
yourself speaking to a Dr Carey or a Dr Grubb,
but whoever you talk to should be able to work with your vet to devise a
treatment
plan.
You should also make a report to the Food & Drug
Administration. Apparently the manufacturers are not obliged to report any
cases of kidney problems to the FDA because renal failure is already
listed in the package insert as a possible side effect, but I believe it
is very important for the FDA to be fully aware of the scale of the
problem.
FDA Consumer Complaints Co-ordinator
has
details of the relevant contacts for each state (at the bottom of the
page).
Canada
The manufacturer's contact number is 1-800-325-9167, though they will only
speak to vets.
There is
interest in using meloxicam for reasons other than pain control, as
follows:
Slowing the Progression of CKD
In light of the
studies mentioned above,
which seemed to indicate that meloxicam might slow the progression of CKD
in cats, a study has recently closed at the University of Kansas
Veterinary Health Center. Results should be available in due course.
There is some evidence that meloxicam may help cats with certain cancers,
including oral squamous cell carcinoma, a cancer that can be very difficult to
treat.
A review of feline oral squamous cell carcinoma
(2016) Pellin M & Turek M Today's Veterinary PracticeNov/Dec
2016 pp24-33 says
"use of
COX-inhibiting anti-inflammatory medications may have several beneficial
effects in cats with SCC, including:
Pain relief
Reduction of neoplasia-associated inflammation and edema
Potentially, anticancer effects, such as disease response or
stabilization."
Robenacoxib is a non-steroidal anti-inflammatory drug
(NSAID). It is somewhat different to meloxicam in that it is
a CoX-2 selective NSAID, i.e. it works effectively on CoX-2 to reduce pain
and inflammation but does not affect levels of CoX-1. See
above
for more about this.
Doses should be administered approximately 30 minutes before surgery.
Robenacoxib should not be used in cats weighing less than 2.5kg (5.5lbs).
USA
Tablets
1 mg/kg (0.45 mg/lb) orally once daily for up to a maximum of 3 days. Use
the lowest effective dose for the shortest time necessary to obtain the
necessary effect for the individual.
Injection
2 mg/kg (0.91 mg/lb) subcutaneously once daily for up to a maximum of 3
days. Subsequent doses can be given via subcutaneous injection or
interchanged with oral tablets.
UK
Tablets
1 mg/kg (0.45 mg/lb) (but with a range of 1-2.4mg/kg) orally once every 24
hours for up to a maximum of 6 days for musculoskeletal disorders.
A single oral treatment may also be given prior to orthopaedic surgery,
and once daily treatment may be continued for two further days
Injection
2 mg/kg (0.91 mg/lb) subcutaneously given 30 minutes before surgery. After
this,
once daily treatment may be continued at the same time every day for up to
two days
Robenacoxib Side Effects
According to
the manufacturer, a number of studies were conducted on robenacoxib in cats,
including a 21-day, 42-day and six-month study at up to 10 times the daily
dose approved for use. Side effects seen in some cats included mild,
temporary diarrhoea and vomiting. Vomiting, neurological signs, intestinal
ulceration, increased liver enzymes and kidney damage were seen at higher
doses.
Since robenacoxib is 30% excreted by the kidneys, it
should be used with caution in cats with CKD, who should be monitored
closely.
Clinical safety of robenacoxib in feline
osteoarthritis: results of a randomized, blinded, placebo-controlled
clinical trial (2015)
King, JN, King S, Budsberg SC, Lascelles BD, Bienhoff SE, Roycroft LM &
Roberts ES Journal of Feline Medicine
and Surgery 9 pp1-11 looked at the safety of using robenacoxib
longer term in 194 cats with arthritis, including some cats (40) with both
arthritis and CKD. The cats who did not receive the placebo were given 1.0-2.4
mg/kg of robenacoxib orally daily for 28 days. The study concludes "Robenacoxib
was well tolerated when administered daily for 1 month in cats with
osteoarthritis, including cats with evidence of concurrent CKD. There was
no clinical indication of damage to the gastrointestinal tract, kidney or
liver."
Close monitoring is required if it is used in cats taking
ACE
inhibitors such as benazepril or
diuretics
because using these treatments together increases the risk of kidney
problems.
Gabapentin is an anti-convulsant, i.e. a medication which is used to
prevent seizures. Although nobody actually knows why, it has also been found to help
with pain, particularly neuropathic (nerve-related) pain or arthritic
pain.
Long-term use of gabapentin for musculoskeletal
disease and trauma in three cats
(2013)
Lorenz ND, Comerford EJ & Iff I Journal of Feline Medicine and
Surgery15(6) pp507-12 looked at the use of gabapentin for
arthritic pain in cats. Results "indicated that satisfactory pain
management was achieved, administration was easy and no obvious side
effects during the period of administration occurred."
Prescribing practices of veterinarians in the treatment of chronic
musculoskeletal pain in cats (2019) Adrian DE, Rishniw M,
Scherk M & Lascelles BDX Journal of Feline Medicine and Surgery
21(6) pp495-506 found that gabapentin was the most prescribed
medication in the survey, being prescribed by 71% of respondents, even
though there is no evidence that gabapentin is helpful for osteoarthritis
in cats.
Wedgewood Pharmacy for Veterinary Practices
says "It appears to be most effective when combined with other types of
analgesic agents, for example NSAIDs, permitting the use of lower doses."
There is a liquid formulation available, but this contains xylitol, which
is toxic to dogs. There is currently no evidence that it is toxic to cats,
and Plumb's Veterinary Drug Handbook says "In cats, at the dosages used
presently, xylitol toxicity does not appear to be a problem with
gabapentin oral solution, but use with caution." Still, some people prefer
to avoid products containing xylitol.
Therefore many people have gabapentin compounded for their cats. However,
people giving a higher dose (see dosing below) can usually cut the 100mg
tablets to an appropriate size.
says "For pain control in cats, doses range from 1.5 to 5 mg per pound
(1.25 to
2.5 mg/kg) every 12 hours. Higher doses (up to 50 mg per cat 1 to 3 times
daily) are recommended by some vets."
Gabapentin does not have long lasting effects (it reaches peak levels in
the blood in cats about 1.5 hours after dosing, and falls thereafter), so
many people find they do need to give it three times a day, which can be
tricky if you have to go out to work.
Gabapentin is excreted via the kidneys so some vets reduce the dose for
CKD patients, who need close monitoring while on the drug. Plumb's Veterinary Drug Handbook (7th Ed.) mentions
with regard to side effects, "Starting the dose at the lower end of
the range and increasing with time may alleviate these effects."
Gabapentin should not be stopped suddenly but gradually tapered down.
Gabapentin Side Effects
Some people believe it may be risky to give anti-seizure medication to a
cat who has never had a seizure, though the doses given for pain relief
are lower than those given when it is used as a seizure medication.
Gabapentin does appear to be safe for cats, with very few side effects.
The primary side effect is sedation.
Ataxia (stumbling, wobbliness) may also be seen. Plumb's Veterinary Drug Handbook (7th Ed.) says "Sedation and ataxia are probably the most likely adverse effects seen in
small animals. Starting the dose at the lower end of the range and
increasing with time may alleviate these effects. In humans, the most
common adverse effects associated with gabapentin therapy are dizziness,
somnolence, and peripheral edema."
Because of its sedative effects, there is actually research into the use
of gabapentin as a mild sedative for cats in certain situations.
Effects of a single preappointment dose of
gabapentin on signs of stress in cats during transportation and veterinary
examination (2017)
van Haaften KA,
Forsythe LRE,
Stelow EA &
Bain MJ Journal of the American Veterinary Medical Association
251(10) pp1175-1181 looked at its effectiveness for vet visits. The
study states "Sedation was a common effect of
gabapentin administration, and ataxia, hypersalivation, and vomiting were
also reported. All effects resolved within 8 hours after gabapentin
administration."
Plumb's Veterinary Drug Handbook (7th Ed.) says "Because gabapentin is
eliminated via renal routes (practically 100% in humans), it should be
used with caution in patients with renal insufficiency."
Nerve growth factor (NGF) is present in the body where there is
inflammation or injury, and contributes to pain from such conditions.
Previous research has shown that neutralising antibodies against nerve
growth factor are effective painkillers for rodents, chronic pain in
humans and arthritis in dogs.
A feline-specific anti-nerve growth factor antibody
improves mobility in cats with degenerative joint disease-associated pain:
A pilot proof of concept study (2016) Gruen ME, Thomson AE,
Griffith EH, Paradise H, Gearing DP & Lascelles BD Journal of Veterinary Internal Medicine
30(4) pp1138-1148 examined the efficacy of an anti-NGF antibody called NV-02
(frunevetmab) for arthritic pain and mobility
problems in cats.
The study concluded "These pilot data demonstrate a 6-week duration
positive analgesic effect of this fully felinized anti-NGF antibody in
cats suffering from DJD-associated pain." The treatment appeared to have
no side effects, with no apparent effect on kidney function.
Anti-nerve growth factor monoclonal antibodies for
the control of pain in dogs and cats
(2019)
Enomoto M, Mantyh PW, Murrell J, Innes JF & Lascelles BDX
Veterinary Record184(1) p23 explains more about this treatment
and concludes "Overall, the rationale for using anti-NGF therapy in
several pain conditions is strong" but states that further research is
needed.
Painkillers: Not Recommended
The following painkillers are not recommended for cats.
Aspirin is a non-steroidal anti-inflammatory drug. Aspirin can be toxic to cats, who can only
metabolise it very slowly, so it is not usually used as a painkiller in
cats.
Nevertheless, it is occasionally used to
treat heart problems when the benefits outweigh the risks.
In such cases it is usually only given in very low doses once every three
days.
Carprofen is a non-steroidal anti-inflammatory drug used to treat arthritis in dogs. The manufacturer
advises against using it in cats, so I would not use it.
TREATING YOUR CAT WITHOUT VETERINARY ADVICE CAN BE
EXTREMELY DANGEROUS.
I have
tried very hard to ensure that the information provided in this website is
accurate, but I am NOT a vet, just an ordinary person who has lived
through CKD with three cats. This website is for educational purposes
only, and is not intended to be used to diagnose or treat any cat. Before
trying any of the treatments described herein, you MUST consult a
qualified veterinarian and obtain professional advice on the correct
regimen for your cat and his or her particular requirements; and you
should only use any treatments described here with the full knowledge and
approval of your vet. No responsibility can be accepted.
If your cat
appears to be in pain or distress, do not waste time on the internet,
contact your vet immediately.
This site was
created using Microsoft software, and therefore it is best viewed in
Internet Explorer. I know it doesn't always display too well in other
browsers, but I'm not an IT expert so I'm afraid I don't know how to
change that. I would love it to display perfectly everywhere, but my focus
is on making the information available. When I get time, I'll try to
improve how it displays in other browsers.
This site is a labour of love, from which I do not make
a penny. Please do not steal from me by taking credit for my work.
If you wish to
link to this site, please feel free to do so. Please make it clear that
this is a link and not your own work. I would appreciate being informed of
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