What is Diabetes?





Diabetes and CKD





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What You Need to Know First

Alphabetical Index


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What Happens in CKD

Causes of CKD

How Bad is It?

Is There Any Hope?

Acute Kidney Injury



Nausea, Vomiting, Appetite Loss and Excess Stomach Acid

Maintaining Hydration

The Importance of Phosphorus Control

All About Hypertension

All About Anaemia

All About Constipation

Potassium Imbalances

Metabolic Acidosis

Kidney Stones



Coping with CKD

Tanya's Support Group

Success Stories



Alphabetical List of Symptoms and Treatments

Fluid and Urinary  Imbalances (Dehydration, Overhydration and Urinary Issues)

Waste Product Regulation Imbalances (Vomiting, Appetite Loss, Excess Stomach Acid, Gastro-intestinal Problems, Mouth Ulcers Etc.)

Phosphorus and Calcium Imbalances

Miscellaneous Symptoms (Pain, Hiding Etc.)



Blood Chemistry: Kidney Function, Potassium, Other Tests (ALT, Amylase, (Cholesterol, Etc.)

Calcium, Phosphorus, Parathyroid Hormone (PTH) and Secondary Hyperparathyroidism

Complete Blood Count (CBC): Red and White Blood Cells: Anaemia and Infection

Urinalysis (Urine Tests)

Other Tests: Ultrasound, Biopsy, X-rays etc.

Renomegaly (Enlarged Kidneys)

Which Tests to Have and Frequency of Testing

Factors that Affect Test Results

Normal Ranges

International and US Measuring Systems



Which Treatments are Essential

Fluid and Urinary Issues (Fluid Retention, Infections, Incontinence, Proteinuria)

Waste Product Regulation (Mouth Ulcers, GI Bleeding, Antioxidants, Adsorbents, Azodyl, Astro's CRF Oil)

Phosphorus, Calcium and Secondary Hyperparathyroidism (Calcitriol)

Miscellaneous Treatments: Stem Cell Transplants, ACE Inhibitors - Fortekor, Steroids, Kidney Transplants)

Antibiotics and Painkillers

Holistic Treatments (Including Slippery Elm Bark)

ESAs (Aranesp, Epogen etc.) for Severe Anaemia

General Health Issues in a CKD Cat: Fleas, Arthritis, Dementia, Vaccinations

Tips on Medicating Your Cat

Obtaining Supplies Cheaply in the UK, USA and Canada

Working with Your Vet and Recordkeeping



Nutritional Requirements of CKD Cats

The B Vitamins (Including Methylcobalamin)

What to Feed (and What to Avoid)

Persuading Your Cat to Eat

Food Data Tables

USA Canned Food Data

USA Dry Food Data

USA Cat Food Manufacturers

UK Canned Food Data

UK Dry Food Data

UK Cat Food Manufacturers

2007 Food Recall USA



Intravenous Fluids

Subcutaneous Fluids

Tips on Giving Subcutaneous Fluids

How to Give Subcutaneous Fluids with a Giving Set

How to Give Subcutaneous Fluids with a Syringe

Subcutaneous Fluids - Winning Your Vet's Support




Heart Problems



Polycystic Kidney Disease (PKD)


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The Final Hours

Other People's Losses

Coping with Your Loss



Early Detection



Canine Kidney Disease

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Home > Related Diseases > Diabetes



  • It is not uncommon for a CKD cat to also have or develop diabetes.

  • The dietary needs of a diabetic cat may seem incompatible with the needs of a CKD cat but the diabetes must take precedence.

What is Diabetes?                                                                                               Back to Page Index


Diabetes mellitus is a disease in which not enough insulin is produced by the pancreas, or the cat’s body cells do not properly process insulin which the pancreas has produced. Insulin is a hormone which enables the body to process food and to produce energy from it. If this mechanism is faulty, the cat develops hyperglycaemia (high blood sugar levels), which eventually leads to high sugar levels in the urine (glucosuria).


There are two forms of diabetes mellitus, uncomplicated and diabetes with ketoacidosis. Cats with the former may only have mild symptoms, at least in the early stages, but cats with ketoacidosis are usually very ill, and may die if not treated promptly. 


Obesity in cats, as in humans, is a strong predisposing factor for diabetes. Cats who are on corticosteroids may also develop diabetes, but this may disappear once the steroids are stopped (which should always be done gradually). Going into remission is relatively common in cats with well controlled diabetes, even if they are not on steroids. Predictors of clinical remission in cats with diabetes mellitus (2010) Zini E, Hafner M, Franchini M, Ackermann M, Lutz TA & Reusch CE Journal of Veterinary Internal Medicine 24(6) pp 1313-21 found that 50% of cats in the study went into remission and that this was more common in older cats.

Feline diabetes mellitus: from diagnosis to therapy (2009) is a helpful article by Dr DL Zoran.

Feline diabetes - five principles breed success (2009) is an article by Dr Gary Norsworthy in the October 2009 edition of Veterinary Practice News.


Symptoms                                                                                                           Back to Page Index


The increase in sugar in the urine causes polyuria (increased urination) and polydipsia (increased drinking). Diabetic cats also tend to lose weight, so to some extent the symptoms of diabetes may resemble those of CKD, although there is one noticeable difference, namely that diabetic cats tend not to lose their appetites – they lose weight despite continuing to eat, and may in fact eat more (this can also be a symptom of hyperthyroidism).


However, more advanced diabetes may cause lack of appetite, plus poor coat quality, vomiting and dehydration and occasionally breathing problems. Bladder infections are also relatively common because of the sugar in the urine, and inappropriate elimination may occur.


You may also see a plantigrade posture (as demonstrated by Ollie to the left), where the cat walks on his/her hocks instead of his/her feet: this is most common in diabetic cats, caused by diabetic neuropathy, where the nerves in the legs are damaged by the disease, but may sometimes be seen in cats with high phosphorus levels, or with neurological problems from other causes. Ollie did this because of low potassium levels. Since Ollie is so fluffy, you may find this photo on 123catworld clearer.


Long Beach Animal Hospital has a photograph of a cat with diabetic neuropathy doing this (click on Symptoms). Newman Veterinary has a good before and after photo of a diabetic cat with this problem, scroll down a little to Other Common Consequences, then click on Plantigrade Stance (in red font).


 The Mayo Clinic has information about peripheral neuropathy, including that caused by diabetes.


Diagnosis                                                                                                              Back to Page Index


The vet will base the diagnosis on bloodwork, clinical signs, and high levels of sugar in the blood and urine on an ongoing basis. Cats who are stressed by vet visits may sometimes have high blood glucose levels, so this is not necessarily a definite sign of diabetes, it is the ongoing nature of the increased glucose level that is important. For this reason, it is a good idea to check fructosamine, which measures concentrations of glucose molecules historically over a period of approximately 2-3 weeks. Lab Tests Online has an overview of the fructosamine test.


Cats with ketoacidosis may have elevated BUN and creatinine levels, which in this situation may not necessarily be a sign of CKD, particularly if phosphorus and potassium levels are normal. Diabetic cats also often have dilute urine unrelated to CKD, and the resulting dehydration may also cause increased kidney values. Once the diabetes is under control, the BUN and creatinine levels may improve. Initially the bloodwork may also indicate liver damage, which should improve as the diabetes is brought under control. 


Treatments                                                                                                           Back to Page Index


Cats with ketoacidotic diabetes normally require hospitalisation including IV fluids and insulin therapy, until they are stabilised; thereafter they will be treated as cats with uncomplicated diabetes.


Cats with diabetic neuropathy often benefit from Vitamin B12 in the form of methylcobalamin. Jasper's Page has more information on this treatment.


Controlling any infection that is present, such as a urinary tract infection, may make the diabetes easier to control.



Uncomplicated diabetes is usually managed by means of insulin injections. Bovine insulin is most similar genetically to feline insulin, and is readily available in the UK; however, in the USA animal-based insulins are often imported from the UK and may be relatively expensive. The insulin is administered once or twice daily, and cats vary in their response, so the amount and the frequency are determined by checking blood glucose levels. This needs to be done every few hours at first and may be done in hospital initially, but gradually the frequency of checks can be reduced to once or twice a day (see monitoring). If the diabetes is properly controlled, the earlier symptoms should disappear.


Cornell University College of Veterinary Medicine has a series of videos covering all aspects of diabetic cat care, including how to give insulin, monitoring your cat, and recognising and treating hypoglycaemia. 


Oral Medication

Sometimes diabetic cats can be treated with an oral medication called glipizide instead of injectable insulin. However, only about 30% of diabetic cats respond to glipizide, and cats taking it must be carefully monitored because the drug can damage the liver. In any event, most cats are far easier to inject than to pill.



Diabetic cats also require their diet to be monitored. Your vet can advise you on frequency of feeding, but usually cats receiving insulin twice a day are fed half their daily food ration each time; free feeding is not normally appropriate for diabetic cats. Cats receiving glipizide are normally fed several small meals a day.


High fibre, high complex carbohydrate diets (such as Hill’s w/d diet) are sometimes recommended for diabetic cats because it used to be believed that they might help to control blood glucose levels. However, cats have a low natural requirement for carbohydrates, and more recent research in fact indicates that higher protein, higher fat and lower carbohydrate diets may be more suitable for diabetic cats. Suitable foods for this approach include Purina DM Dietetic Management veterinary formula (not currently available in UK), and kitten foods, which are usually high in protein and fat. Hill's have a similar food called m/d (click on Prescription Diet, then on Cat, then on m/d), which also has a relatively low phosphorus level of 0.7% on a dry matter analysis basis. It is important to try to moderate phosphorus intake for cats with both CKD and diabetes, and if necessary, phosphorus binders will need to be used.  


There is some debate as to whether dry food is appropriate for diabetic cats. Indoor confinement and physical inactivity rather than the proportion of dry food are risk factors in the development of feline type 2 diabetes mellitus (2009) Singerland LI, Fazilova VV, Plantinga EA, Kooistra HS & Beynen AC Veterinary Journal 179(2) pp247-253 found no evidence that dry food diets in themselves cause diabetes in cats. However, some diabetic cats are so sensitive to carbohydrate that they need less insulin, or in a few cases stop needing it all together, when switched to a low carbohydrate diet. Generally speaking, canned foods are much lower in carbohydrate than dry foods, so canned foods low in cereals and added sugars may be helpful in such cases, but dry foods may be less suitable because they tend to have a high carbohydrate content.


Diet changes should be made gradually if a cat is already taking insulin, and blood glucose levels should be carefully monitored, because sometimes there is a dramatic drop in blood glucose in response to reduced carbohydrate, with a possible risk of an overdose of insulin (see hypoglycaemia).


Comparison of a low carbohydrate-low fiber diet and a moderate carbohydrate-high fiber diet in the management of feline diabetes mellitus (2005) Bennett N, Greco DS, Peterson ME, Kirk C, Mathes M, Fettman MJ. Journal of Feline Medicine and Surgery Nov 3 found that the diabetic cats in this study who were fed the low carbohydrate-low fibre diet were significantly more likely to stop needing insulin than the cats fed the moderate carbohydrate-high fibre diet.

Diet in the prevention of diabetes and obesity in companion animals (2003) Rand JS, Farrow HA, Fleeman LM & Appleton DJ Proceedings of the Nutrition Society of Australia discusses how dietary changes may help with diabetes control.


Monitoring                                                                                                           Back to Page Index


Urine glucose is only really useful for initial diagnosis – healthy cats do not have glucose in their urine – because it is too imprecise a measure to make proper decisions about insulin dosage. However, you will probably need to check urine ketone levels using dipsticks (Ketostix, available from pharmacies). Even a trace of ketones is a cause for concern and warrants an immediate vet visit.


Home Blood Glucose Testing

You will also need to monitor your cat's blood sugar levels, and may wish to do this at home using a glucometer (available from pharmacies for use by human diabetics) – home monitoring is much cheaper for you and less stressful for your cat. The blood can normally be taken from the ear (make sure it is warm) using a sterile lancet, and only a tiny amount is required, though many UK vets are unfamiliar with this approach. Generally speaking, a cat is considered regulated if his/her blood glucose consistently remains in the 5-15 mmol/l (US: 100-300 mg/dl) range.


Sometimes cats are started on too high a dose of insulin, which leads to a sudden drop in blood sugar levels, and the body reacts to this by releasing glucagons which raise blood sugar levels again. It thus appears, based on spot checks at the vet's, that the cat requires even more insulin, when in fact the opposite is the case. This is known as the Somogyi Effect. Home blood glucose monitoring gives more accurate results and can help you to avoid such problems. 


Veterinary Partner has step by step instructions for home blood glucose testing with a slide show guide.

Sugar Cat Harry's Website has detailed information on home blood glucose testing.

Feline Diabetes has information on the Somogyi Effect.



As a general rule, too much insulin is far more dangerous for a diabetic cat than too little, and may cause low blood sugar (hypoglycaemia). Symptoms include weakness, lack of co-ordination, convulsions and coma. The cat should be offered food immediately if still able to eat, or you may need to rub corn syrup or powdered glucose on the gums (in UK you can also buy a human OTC diabetic product called Hypo-Stop); otherwise you should contact your vet urgently. You will need to discuss your treatment programme with your vet following an incident of hypoglycaemia. 


Gorbzilla has information on hypoglycaemia.


Diabetes and CKD                                                                                              Back to Page Index

If you are dealing with both diabetes and CKD, it is more important that the diabetes should be regulated, and in fact once this is achieved, you may find the CKD improves too. Please also see diagnosis above. 


People dealing with both diabetes and CKD are sometimes anxious because it appears that the protein requirements of the two conditions are incompatible, but in fact low protein is not necessarily essential in the treatment of CKD, see Nutritional Requirements and diabetes diet for more information.


A dehydrated cat may respond less well to insulin, and many people have found that once sub-Qs are begun, the insulin seems to work more effectively, sometimes with longer duration than was previously the case.


Anecdotal evidence suggests that diabetic cats with CKD may do less well on benazepril (Fortekor) than cats with CKD only.


Links                                                                                                                     Back to Page Index


General Overviews

Cornell University College of Veterinary Medicine has a series of videos covering all aspects of diabetic cat care, including how to give insulin, monitoring your cat, and recognising and treating hypoglycaemia.

Keys to management of diabetes in cats (2011) is a presentation by Dr S Little to the 36th World Small Animal Veterinary Association World Congress which compares the various brands of insulin available and advises on how to adjust insulin dosage.

Cornell University College of Veterinary Medicine has a good general overview.

Washington State University also provides a good overview.

Feline Diabetes Message Board FAQs provide detailed answers to frequently asked questions.

Gorbzilla has lots of practical information, including information in German. 



Feline Diabetes Message Board (FDMB) is a very busy message board, which is part of a helpful website too.

Pet Diabetes Group is a group which covers cats and other species, though it is much less active than the FDMB; it also has an associated website.

Feline Diabetes Group is a group for people dealing with diabetes in cats.


Back to Page Index

This page last updated: 16 October 2011

Links on this page last checked: 03 April 2012