Diabetes in Cats

Please note: The most recent medical information is at the top of the page to least current at the bottom.

Diabetes Mellitus

Cats can sometimes be maintained for long periods of time using dietary changes and medical treatment, although it may be preferable to start treatment for diabetes with insulin in all cats and then to try to maintain the cat later without insulin if it looks like that might be possible. There is absolutely no question in my mind that the best way to monitor pets with diabetes to aid in regulating insulin levels is for the veterinary client to learn to monitor blood sugar at home using a blood glucose meter. It appears that about 50% of veterinary clients can manage this task readily and most can manage it with encouragement from their vet and the vet's staff. Some vets are not yet ready to take on this task, though. If your vet is one of those who discourages clients from attempting home glucose monitoring I personally think that you ought to change vets, at least for the pet with diabetes, unless there is a really compelling reason to stay for reasons other than the diabetes treatment. Purchasing one of the newer blood glucose meters that require very small blood samples is best. It can be hard at times to get blood from a pet and they tend to move around a lot during the blood drawing process, making it critical that whatever blood you can get can be utilized quickly. Spend a little extra to get a good glucose meter, such as the One Touch (tm) glucometers and it will pay off over the long run in ease of use. Regulating insulin dosages and blood glucose levels requires a lot of communication between the veterinary client and the vet. It can be a frustrating process that can take months in some cases. There are a few patients who are just extremely difficult to regulate. Despite this most insulin regulation failures are the result of insufficient communication between the veterinarian and the client or insufficient effort on the part of either the vet or the client, or both. It is nearly always possible to regulate insulin with adequate effort on everyone's part. Choosing the type of insulin to use can be confusing. We almost always start with human NPH insulin, either Humalin N (Rx) or Novalin NPH (Rx) because these insulins are widely available and seem to work well for us. It is important to try to stick with an insulin type once good regulation is achieved so it is helpful to use an insulin that is likely to be available when you need it. Some vets prefer PZI insulin and there is now an insulin approved for use in dogs ( Vetsulin Rx) that is pork based and may work more consistently for dogs since pork insulin is closer to dog insulin than the human products. In addition, glargine (Lantus Rx) seems to work better for some cats than other types of insulin. Since it is also a human product there is a good chance that it will be available at all times, as well. Don't change insulin types willy-nilly, but remember that there are alternatives if regulation is proving to be very difficult. A blood glucose curve is a plot of blood sugar levels during the day. It is generally done by obtaining a blood glucose level at the time of the morning meal and every 2 to 4 hours afterwards for at least 12 to 16 hours. Plotting the blood glucose numbers on a chart allows visualization of when the level is too high, too low or just right. The pattern of rises and falls in blood glucose allow the veterinarian or the client to see if the problem is an overdose of insulin, an underdose of insulin or resistance to the effects of insulin. This is valuable information that is essential to really good regulation of insulin levels. Even though I strongly believe in the value of blood glucose monitoring at home, it is possible to monitor sugar levels using urine testing when abolutely necessary. Monitoring urine levels doesn't work as well as monitoring blood sugar levels but is better than not monitoring at all for those who are challenged by drawing blood from their cat. This is probably veterinary heresy but I treat pets with insulin when the owners are willing to give the insulin injections twice a day but unwilling to pay for additional lab testing or won't attempt getting blood or urine for testing at home. I am willing to do this because the pet is going to die much more quickly, in most cases, if insulin is not used. We explain how to monitor behaviors such as drinking, urinating, appetite and attitude to evaluate whether blood sugar is too low or too high and hope for the best. People get pretty good at recognizing signs of high and low blood sugar over time. If their pet makes it to a stable situation there is a good chance of long term survival as long as insulin continues to be provided. Sometimes, when there is early success, these folks start to believe their pet might make it and go ahead and purchase home glucose monitors or work with us in other ways to monitor their pet's diabetes. Mike Richards, DVM 08/2005

Chromuium picolinate and vandium used in treating feline diabetes

Question: Hi Dr Richards: I have a 7 yr old neutered male with serious eye problems (herpes, uveitis, glaucoma, corneal ulcers) who is also FIV+. I dont know if it was all the prednisone orally and via eye drops he was/is on (now ndrops and 5 mg every other day) but he developed diabetes. He is now on Glipizide 5mg am and 2.5 mg pm. My usual vet is retiring and the new one is recommending chromium picolinate 200 ug per day and also vanadium. The literature I have read indicates vanadium is not widely used and a study inIndia in rats showed it caused death in a large number of cases. Could you tell me if I should start the cr picolinate at 200 ug right off the bat or should I start at a low divided dose(50 ug a day) and work up from there?? Could you tell me when in 2000 there was an article in JAVMA about cr and vanadium? It might have been 4 2000 0r 5 /2000. I have also purchased a glucose meter and am slowly learning how to use it(practicing on myself) in the hopes it will be less stressful for BIg TOm to have his glucose measured at home. Do you recommend the use of vanadium?? Is it OK to start with the cr picolinate at 200 ug or should i start at a lower dose and work up?? I have discovered the website feline diabetes, are there any others?? thanks, catwoman. Answer: C- Both chromuium picolinate at 200ug/day per cat and vanadium have been recommended for cats to aid in control of blood sugar levels when insulin is being used, but I don't think that there is supporting evidence for the usefulness of chromium. I do not know of any reason not to use these products with the oral hypoglycemic agents. Vanadium at a dosage of 0.2mg/kg/day was used in one study and Drs. Greco and Behrend recommended using 1/2 of a Super Vanadyl Fuel (tm) capsule per day per cat in an article in the Compendium on Continuing Education in May 2000. There was also an article in the March 2000 Veterinary Medicine about this use by Patricia Dowling. I was unable to find a reference from the AVMA Journal during the time period that you mentioned by searching the AVMA database but sometimes I have a hard time matching keywords on the AVMA site. The Compendium had a really complete review of feline diabetes. They did not recommend starting the dosage of the medications gradually. I think that there have been problems with vomiting and inappetance associated with vanadium use and one case of kidney failure in a cat that seemed to reverse on withdrawal of the vanadium, based on postings on the Veterinary Information Network (tm). Mike Richards, DVM 3/5/2002

Diabetic neuropathy

Question: Dear Dr. Mike, Wow! Thanks for your quick response. That was just great. I took my cat to the vet's again yesterday, after I freaked out on the phone This time, I saw an associate I had never met before. He said to put Victor on the Purina DM immediately. (Only 3/4s of a cup a day! Victor will be one hungry kitty!) The cat's bsg was close to 500 yesterday, at what was supposedly the peak time for the PZI. This vet likes PZI and wants to continue its use. He kept the dose at 11 units twice daily. He also gave me the Glucotest granules to put in the litter. I am to monitor urine output for the week. I am to call everyday with the Glucotest results. Then the vet will determine if the insulin needs to be adjusted. Victor will now be fed only twice a day, with his shot. I thought this would be a major problem, but, so far, he is really a lot livelier and not urinating as much. I can tell he's hungry because he keeps following me around. But he seems to be doing ok. He even jumped onto the bed this morning to be petted, which he hasn't done in a long time. He couldn't knead with his front paws, though. I sure hope that comes back. The neuropathy seems a little bit better this morning as well. At least Victor can walk more than 4 feet. Is it possible that he can look better and act livelier and the neuropathy can persist? My vet said the neuropathy damage was completely reversible. Right? As to stress, yes, Victor is the original scaredy cat. He has always flinched at everything and hisses easily. I asked the vet if I could do the blood monitoring at home, and he said it would be very difficult for me. Maybe I can push that some. Its interesting that you say you rely on the bsg testing. My first vet held this opinion, but vet 2 liked fructosamine levels. Even though Victor's fructosamine level was a 4, his sugar was way out of whack. The vet did mention that he would do another curve soon. He took blood for a CBC work-up yesterday. He is concerned about liver and kidney functions. Victor had been given a cortisol test a while back. The results were normal. I told the vet that when the PZI had arrived by FedEx it was not cold at all. We were in the middle of a heat wave. The lab sent it overnight, but it still wasn't cold. It has arrived before with the ice packs still a little frozen. I wondered it this could have affected the PZI's potency, but the vet felt it would not be a significant factor. Especially since Victor had had one bsg test under 300 while he was on that batch of PZI. So, I will observe and treat for another week. If there is no improvement, I will ask for a referral, as you suggest. I am just so upset that more than 3 months have gone by without any improvement. Thanks for your help. I'll keep you posted. Irene Answer: Irene- It often takes diabetic neuropathy some time to completely go away after blood glucose is well controlled. I am guessing, but I think there is usually some residual signs of this for 4 to 6 weeks after we get glucose levels well controlled in moderate to severely affected cats. The clinical signs are very meaningful so the way he feels is a good sign. Hopefully that will continue. I would be concerned about the insulin but not overly concerned if it seemed to be working. I can't remember the exact duration that insulin can go unrefrigerated but I think it is something like 30 days based on the package insert from HumalinN (which I am recalling totally from memory). Good luck with this. Mike Richards, DVM 8/8/2002

Vomiting in Diabetic cat

Question: Hi Dr. Mike:

I have a 12 year old spayed female cat who has been diabetic now for 5 years. I currently give her 3 units twice a day of PZI insulin. I recently came across a problem that's stumping me and her vet. Every night for the past 2 months, she has been vomiting anywhere from 4:00 to 6:00 in the morning. Then about 3 to 4 days a week, she vomits up all her breakfast. She never vomits up her dinner. Her vet took all kinds of tests imaginable and they all appear normal. So he recommended that I only feed her canned WD and give her 2 full syringes of Laxatone every night before I go to sleep (which by the way surprisingly doesn't effect her blood sugar). The only thing he feels he can come up with is that she has furballs. Well, that isn't working, she still vomits at that hour of the morning. She doesn't vomit up any food, just a white foamy kind of substance or a yellowish substance. The only thing I could think of is that she becomes nautious when her stomach gets empty. So I feed her some WD before I go to sleep about 11:00 p.m., but that doesn't work either -- she still vomits at that weird hour. Her feeding schedule is 6:30 a.m. for breakfast and 5:30 p.m. for dinner. Dr. Mike, can you figure out why she is vomiting only in the morning? I appreciate any help you can offer.


Answer: Janice-

It can help a great deal to go to four feedings a day for cats with diabetes, but that is hard to keep up all the time. The recommended way to do this is to feed 1/3rd of the daily feeding with the morning injection, 1/6th midway between the morning and evening insulin, then 1/3 with the evening insulin and then 1/6 of the total intake prior to bedtime. This helps to even out the sugar levels. We have had one or two cats who seemed to do a lot better on Purinas DM (tm) food. This food is much different than w/d. Higher fiber, complex carbohydrate diets seem to be helpful for diabetes in dogs (and probably people) but the higher protein and fat in the Purina diet is supposed to help cats with diabetes more, at least according to studies by Purina and some independent investigators. The biggest problem that vets seem to have with this food is palatability-- cats don't always seem to like it.

There is also a reasonable probability of concurrent inflammatory bowel disease, pancreatitis or liver disease as a cause of the vomiting. Checking for these conditions with lab work would be good idea. In some cases, X-rays, ultrasound examination or endoscopic examination of the digestive tract might be necessary to make a diagnosis but you can determine the extent to which you wish to pursue these things based on what is happening. It is possible to treat most for these problems. In some cases kidney failure that is developing independently of the diabetes can lead to vomiting.

We also see some cats with diabetes that seem to have vomiting due to high blood pressure. We can't measure blood pressure accurately in our practice so we are basing this assumption on clinical signs of high blood pressure and response to therapy. It is possible that the medications might have some other beneficial effect or that the vomiting has cleared up for other reasons in these patients since we haven't done anything like a controlled study. But just in case your vet sees any other signs of high blood pressure it would be worthwhile to consider this possibility.

I would try the additional meals first, just as your vet suggested. It seems to work for some patients. After that I think I'd want to do a serum chemistry panel and look for problems that just aren't obvious clinically. Then I think it gets harder to decide what direction to go in. I guess we probably treat for inflammatory bowel disease to see if there is a response most often at this time but we change that approach frequently based on the clinical exam findings.

Good luck with this.

Mike Richards, DVM 7/2/2001

Diabetes in elderly cat

Question: Dear Dr. Mike Richards, DVM, My cat Willie is almost 18 years old. In December of 2000, she became diabetic while I was on vacation. When I returned in January, I noticed that she had lost a lot of weight. She has always decreased her eating while I was away in the past, and she was happy to eat now that I was home so I let it be. However, I noticed after about a week she wasn't getting better. I took her to the vet, and they did some blood tests. That night she became very ill, and the next day when the vet notified me of the results of the blood tests, we started her on 1 unit of Humulin Ultralente. That night I ended up taking her to the emergency vet as she was breathing hard and moaning. She had become keto-acidoic. She spent the next four days on IV's and stayed in the hospital. We started her on 1 unit of Ultra-lente in the morning, and 2 units at night. I was having to force feed her, and she had neuropathy very bad. After several weeks, she started eating again and her neuropathy began to disappear. I have gotten her on a feeding schedule of eating 1 Tbsp of W/d wet at 7:00am and 7:00pm, with 1/2 cup dry W/d in the morning to eat all day, and 1/4 cup in the evening. We have since had to change to Humulin NPH insulin, as we weren't having any results with the Ultralente. Until last week, we were all the way up to 6 units 2X a day, but she was always over 500 when tested (8:00 am and 5:00pm). She recently had a urinary tract infection, and had severe diarrhea from the antibotic for over a week. On March 5 when taking her in for testing, she was at 74, so my vet wanted to keep her for the day since Willie wouldn't eat. 2 hours later she was at 8. She didn't show very many signs of being hypoglycemic, which made me think that maybe she was always going too low, and that's why she was always so high at the times we were testing her, since they were towards the end of her injections. She went down again on March 8 to 16. Again, the only symptom she showed was being tired. We reduced her insulin to 3units in the morning and 2 at night. I suggested to my vet that we test around 2:30pm, when her shot was approximately 7 hours old. We did so on March 9, and she was at 164. We went through the weekend, and we stopped the antibiotic to help her stomach feel better. She began eating better, and the diarrhea went away. Monday when I brought her in at 2:30pm she was back up to 360, and at 5:00pm, she was at 541. She has already been tested for Cushing's disease, (back in the very beginning when we were having problems with the Ultralente, my vet worried about this being a contributing factor), however, she tested negative. She has never been ill in her life, and other then feeling bad at the beginning hours and ending hours of her shot, she seems fine. She drinks a lot of water, and she eats compulsively at the beginning of her injections (while she is really high) or she won't eat at all. I really want to get her regulated because she is old, and I know this puts so much strain on her body, especially her kidneys. I feel that my vet is out of ideas, and I am not sure what to do. I thought at first that maybe she was insulin resistant, but then she was crashing. However, it seems whenever she starts to eat again, she skyrockets. I have read that things such as cinnamon and brewer's yeast have been known to help with lowering blood glucose levels in humans, but my vet would rather we did not try "supplements". I really don't know what else to do. When she crashed the first time, my vet ran some tests and found reticulocytes in her urine, and that she was low on potassium. My vet stated that this could be the beginning of kidney failure, but that the anemia could also be from her losing blood from her urinary infection. Couldn't the low potassium be from the dehydration and the diarrhea? Her original blood work from January came back with her kidneys being at normal levels, showing only mild signs of aging. Also, I had read that high fiber diets inhibit iron absorption in humans, and Willie is eating only W/d. I mentioned this to my vet and she said it wouldn't happen in cats, though. I feel as though I am at a dead end, and that my vet is beginning to think that regulating Willie will not be possible, as she told me the other day that I need to start thinking about what we are doing. I do not want to make Willie suffer, but she only acts like she isn't feeling good during the time when the insulin is wearing off, and I feel that if we were able to attack this more aggressively, we could go >somewhere. She would rather I did not do any glucose monitoring at home as she stated it is difficult, but Willie growls now when I bring her to the vet 2X a day, 2-3X's per week. I bought some Chemstrip urinalysis sticks from my vet, but they always show that the glucose is over 1000 (Specific gravity 1.020, and pH5). Any ideas or suggestions you may have will be deeply appreciated. Thank you, Jennifer

Answer: Jennifer-

I hope that you have had a little more success over the last two weeks than your were having but just in case, these are the things that I can think of to do.

The first thing is to keep in mind that you are helping Willie a lot by giving some insulin, even if you are not ever able to get her fully regulated. I have had diabetic patients whose owners we had difficulty communicating with or who would not make much of an effort to regulate the insulin whose cats lived for several years just because it is better to be helping some than not helping at all. So if it takes a while to regulate Willie, that is OK.

The next thing is that I disagree very strongly with your vet about home testing for diabetes. This works very well in our practice and I think that it is much more likely to be an accurate assessment of the glucose levels at home because the stress of traveling to the vet's and perhaps even staying there for the day, is eliminated. We use the following technique to obtain the blood for testing and almost all cats will allow this testing.

1) We use a 27 gauge needle as our "stylet" to prick a vein with. This is a very small gauge needle and it is not usually uncomfortable for the cat when the artery or vein is poked with the needle.

2) We shine a flashlight through the ear with the flashlight held against the unhaired portion of the ear. It is almost always possible to see the little arteries and veins along the edge of the ear.

3) We prick directly into one of the visible blood vessels. This produces a small drop of blood that is easy to pick up with the siphoning blood sticks or with a disposable dropper and then placed on the test strip. For long haired cats it may be helpful to spread a very thin layer of Vaseline over the edge of the ear prior to making the stick into the blood vessel.

4) I think that any of the blood sugar monitors (glucometers) that you can buy at your favorite pharmacy will work. Some are easier to use than others, though. I think that ones in which the test strip siphons up the blood are good but remember that the price of testing over the long run is most affected by the price of the test strips, so check out prices of these for the glucometers when considering them. It might be better to be a little inconvenienced to save on costs, if cost is a factor in your decision making.

Almost all of our clients can learn this technique. Some cats aren't friendly enough to allow any testing and some clients are a little too squeamish but most can do this.

The major advantage of home testing is that it allows a blood glucose curve to be evaluated. If a blood sugar test is done every two to four hours for twelve to sixteen hours, it is usually possible to tell if there is an overdosage of insulin leading to very low lows and very high highs, or if there just isn't adequate insulin being administered at any time during the day. Once this is known, it is possible to adjust the insulin dose accordingly.

I think that most of our diabetic cats need between six and twelve units of NPH insulin twice a day, but some do require less and some more. Our record low was a patient who only needed 1/2 unit of insulin twice a day but would become symptomatic of diabetes without this dosage and our record high for a cat is 22 units twice a day.

If you can't work out home blood testing with your vet you could try to do more systematic urine testing. If there is sugar in the urine throughout the day, it is likely that you are not ever reaching an adequate dosage. If there are times when there is no sugar at all in the urine and other times when the sugar levels are very high in the urine, it is more likely that you are over dosing the insulin or underdosing it (and the timing might help in distinguishing these two events). Personally, I think that blood testing is much more accurate as it gives "up to the minute" blood sugar information while sugar in the urine just tells you there was a time during the day when the blood sugar was not being adequately controlled.

In cats, it may be better to use a low fiber diet that is higher in protein and fat calories than to use a high fiber diet. It also helps a great deal if you can spread the calorie intake out over as much of the day as possible -- so several small meals is better than two big ones.

Supplementing potassium may be helpful in making your cat feel better and is usually safe even if it isn't necessary. Vanadium may help to stabilize insulin dosing, as well. I am on the road (literally -- working on my laptop in the car) and I don't have the vanadium information with me, but I think it is on the web site. This has been written up recently in the Compendium for Continuing Education and I think in Veterinary Medicine (the journal), so your vet might have access to these articles if she needs some persuasion to consider this supplement.

Mike Richards, DVM 3/28/2001

Purina DM Formula (tm) diet for diabetic cat

Question: Dr. Richards,

Thank you for your thorough responses to my previous questions. Your advice on the insulin dosage versus weight appears correct, as our cat has responded wonderfully to 9 units of insulin, twice per day. (I noticed you indicated this was a hot topic recently) In fact, she has gained all her weight back and is as playful as ever.

My question concerns the recent "breakthrough" that Purina claims for its new DM formula cat food for diabetic cats. (Is it dry or wet?) I thought I would ask your opinion on the product before investing in it. Here is the company link for the product, if you are interested. http://www.purina.com/institute/news.asp?article=232

Thanks again for all your help. John

Answer: John-

The Purina DM Formula (tm) diet is made to conform to some of the more recent information on cats and their abilities (or inabilities) to utilize complex carbohydrates. Cats are different than dogs and have less ability to utilize carbohydrates, making the usual dietary recommendations for dogs, of increasing complex carbohydrates and fiber, less ideal for cats. So, in theory, the higher protein and fat percentages in the Purina DM Formula should be a better diet for diabetic cats based on this information.

We have not tried this diet in our practice but I have seen several posts about it on the Veterinary Information Network (tm) and have discussed it with other vets. The general experience seems to be that the diet is not very palatable (cats don't like it much) but if they will eat it, there does seem to be a decrease in insulin requirements and at least one or two cats that I have heard of have been able to maintain normal blood sugar levels on the diet without insulin. The decrease in insulin requirement does mean that the blood sugar has to be watched very carefully as the diet is initiated and that it is a good idea to make a very gradual transition to this diet.

This diet is not appropriate for cats with kidney failure or liver failure due to the high protein levels.

The diet is available in canned formulation only (or at least that was the case as of Oct. 1, 2000, which is the last feeding guide I have from Purina.

Hope this helps.

Mike Richards, DVM 1/24/2001

Taking blood from a diabetic cat - also treating rodent ulcers

Question: Dear Dr. Richards,

Did not know how to post a question without replying to your wonderful overviews of pet problems. I don't think you will remember that you did answer me once before about a depo induced diabetic cat. This one incident cleared up and I was so stupid to give her not one, but two more shots to give her some relief from her very, very, very virulent rodent ulcer. Voila, she is now a diabetic again. The first depo shot is now 8 weeks gone, and the second 4. We have a new vet now (and maybe unfortunately), but she is taking blood from the jugular, which is another question, is that the norm? We have been giving this 12 year old cat PZI (5 units) for about 4 weeks now, and with this jugular blood in this vet's machine, we are only getting higher, and higher BG results. Today it was above 500, but Medley is acting quite normally. Would appreciate an opinion as soon as you can.


Answer: Anita-

I don't know if drawing blood from the jugular vein is the most common method, but it is a method that many vets favor in cats. This will have some impact on the glucose measured using hand-held glucometers, since they are calibrated with capillary blood in mind, but that is also true of blood drawn from other veins. I think this is why glucometers tend to read a little low (around 10% less than typical in-office blood machines) when used for pets. If your cat objects strongly to the blood drawing procedure, that may be influencing the blood glucose results. Cats can raise their glucose levels significantly when they are stressed. We have one cat in our practice whose blood sugar is typically 275 in our office, but who never has glucose in the urine when tested at home. Since glucose should spill into the urine when serum levels are about 180 gm/dl we are certain that this cat is just releasing glucose into the blood stream due to stress.

If you are only drawing blood once a day, it is also possible that the blood values are falling below normal and then rising rapidly due to this. Varying the time of day the blood is taken can help to point out a problem like this, but doing a blood glucose curve (several samples from the same day) is the best way to figure this sort of problem out.

I have seen some anecdotal reports of success treating eosinophilic granulomas ( a cause of rodent ulcers) using ceterizine (Zyrtec Rx), 2.5 to 5mg twice a day. This is an antihistamine. We have had success in some cats using chlopheniramine maleate (Chlortrimeton Rx) and essential fatty acid supplementation (DermCaps tm or 3V Capsules tm -- and others). Once in a while these are due to contact allergies (wool, plastic) or due to food allergies. An elimination diet or the new hypoallergenic foods (Hills z/d tm) might be helpful if this is the case. These would interfere less with diabetes than the corticosteroids.

Hope this helps some.

Mike Richards, DVM 11/21/2000

Licking behavior in diabetic cat

Question: Dear Dr. Mike,

I wrote to you a while back after I learned my 18 year old male cat had diabetes. We finally got his sugar levels somewhat under control and are in contact with the vet frequently. My question: On two or three occasions, my cat will begin to lick the walls, furniture, etc. At these times he was waiting for me to feed him and I just thought he was excited about wanting to eat and was exhibiting some anticipatory behavior, although very atypical for him. A few days ago, after being fed, he began licking the chair legs, wallpaper, glass cabinet and was difficult to redirect for approximately 20 minutes. He then took a nap and awoke to go back into the room and begin licking everything in sight including the floors as he was walking. I spoke to my vet today and he feels that it is probably some sort of seizure and that if it happens again, to call and possibly get blood work done. Have you heard of this type of behavior? Is it common in older cats? I asked the vet if his sugar levels may be contributing to the behavior, but he didn't feel that it did. I would appreciate any thoughts you may have regarding this.

Thank you very much, Barbara

Answer: Barbara-

There is a condition referred to as a partial complex seizure, in which pets exhibit a behavior such as licking the floor and are hard (or impossible) to distract from the behavior. This is a hard problem to distinguish from a behavioral problem. It is also hard to be certain that it is not occurring for behavioral reasons other than a seizure. In the case of a diabetic pet, I would be most comfortable if I could do a blood glucose curve and make sure that there was not a portion of the day when the blood sugar was lower than it should be or much higher than it should be, since this does seem to affect behavior in some patients. I can't actually remember one licking the floor as a behavior associated with hypoglycemia in any of our patients, but I would still like to rule it out. If that is not the problem, and a general chemistry panel and complete blood cell count also seems normal, I think that it may be really difficult to figure out if there is an underlying cause or to treat the problem. It is really hard to be certain whether partial complex seizures are occurring, so it may be worth a visit to a veterinary neurologist if the behavior continues and if you have a neurologist in your area so the trip isn't too hard on you or your cat. In all honesty, this is a hard condition to treat even if it can be confirmed, so if it is difficult to get a neurologist's opinion, I don't think I'd go to extraordinary lengths to get your cat to a neurologist. It might help if it is easy to arrange, though.

Mike Richards, DVM 10/9/2000

Diabetic cat

Question: Dear Dr. Richards,

This question pertains to our 6.5 year old indoor cat Lucia. Here's a not so brief case history.

On returning from a week long trip several years ago, we found Lucia to have difficulty breathing, so much so we brought her to an emergency room where she stayed overnight. At this point she was diagnosed with asthma and given Prednesone and a bronchidilater. All was well for several years (we stopped the medicine after a week or two and used as needed) until this spring, when her asthma reappeared with a vengeance. She was given Prednesone again for a two week period and again her asthma subsided. After returning from a weekend away this June, we noticed that Lucia had lost weight, was not eating much, and was very lethargic. We brought her to the Vet and was told that she had very high glucose levels and keytones in her urine, so much so that she stayed the weekend for IV treatment and glucose curves. After several weeks on Insulin and Cipro (for the asthma) she seemed well on her way to recovery. Her eating habits, however, changed significantly. She would no longer eat her Nine Lives that she had eaten all her life. In fact she would cycle through different types of food that she would or wouldn't eat. At one point she ate 4 cans of fancy feast a day, but will not eat that anymore. She incessantly begs for table scraps, something she never did before. She seems to cycle between times of not eating at all and eating quite a bit. After her Insulin shot, her ears tend to get very warm and she likes to lay down on cool surfaces (tile, hardwood), as opposed to our bed, where she used to sleep. When we leave for a weekend, she seems to not want to eat at all. At this point, I don't think she has been completely regulated for the correct Insulin level (we're doing 5 units per day of Insulin U), but I can't help but feel there is something else wrong with her. Having read about Pancreatisis, it seems like she might have several of the symptoms. We are bringing her to the Vet for more blood work tomorrow, but so far, they can't find any other problems, aside from the diabetes. Her brother does not have anything wrong with him, so we've ruled out any infectious diseases. Any guidance would be greatly appreciated.

Thanks, John

Answer: John-

Pancreatitis is subtle and difficult to diagnose in cats. It is possible that it is present. Considering the other medical history it is probably more likely that the signs you are seeing are due to the diabetes and/or asthma, though. It is particularly difficult to deal with asthma in a diabetic cat due to the problems with regulating cats when corticosteroids, like prednisone, must be used to treat a secondary condition.

It is a good idea to try to use alternative therapies to limit the amount of prednisone that is necessary to control the asthma. Cyproheptadine is a good thing to try. Bronchodilators help some cats. Having terbutaline (Brethine Rx) on hand to deal with crisis situations might also be a good idea. In most cats with asthma, occasional use of prednisone or some other corticosteroid is likely to be necessary, though.

During the initial few weeks to months of insulin therapy there are often problems with variable appetite and cats will often eat a food one day and then refuse it the next. Over time, as it is possible to adjust the insulin dosage to more closely control the glucose levels, there is usually a point where the cat goes back to a normal eating pattern. Cyproheptadine is an appetite stimulant in cats but it causes depression in the first week or so that it is used in a lot of cats, so that might be part of the problem with the eating pattern, to.

We have not had to deal with sensitivity to insulin very often, but it does occur. We usually have seen pain at the injection site that is consistent, but it would be possible for other signs to occur, such as flushing of the skin, which might be what you are seeing with the ears. Your vet probably would notice this during the time when Lucia is there but do remember to tell him or her about it, too.

One of the hardest problems to deal with in diabetic cats is the effect of things like leaving them at the vets or even when leaving them at home with someone looking out for them. This stresses cats, which makes them release more sugar, changes their eating habits and just makes it generally hard to keep their insulin regulated. This becomes less of a problem over time, as everyone adjusts to the use of insulin, but it is really tough early on when trying to establish the correct insulin dosages.

This is just something that you have to work through and it does take a lot of coordination between you and your vet, so keep in close contact and don't be afraid to ask questions and point out problems. This is going to be doubly true in Lucia's case since asthma requires the same sort of relationship with the vet. Hang in there and things should improve with time.

Mike Richards, DVM 9/14/2000

Diabetes and hairloss

Question: We have been dealing with feline diabetes for a couple of years. Initially, when our 9 year old female was diagnosed, she was regulated on Iletin. I can't recall her dosage, but after 10 months, she had 6 months where she didn't need any insulin at all (confirmed by our vet). At the conclusion of the six months, she showed signs of diabetes again and we headed back to the vet. Unfortunately, at that time, Iletin was being discontinued, so we started on Humulin-U. We do not do blood glucose curves any longer, although until this summer we took her to the vet for them monthly. We did that for a year with no progress on a curve. Her numbers were always very high throughout the day (400+) with an evening crash (under 100)- every time. From her behavior and water consumption, she seems to need around 4 units, but she has really high numbers in her urine sample just before her morning shot. So now we give her 4.5 units of Humulin twice a day. Her evening numbers still are low, but when we have reduced insulin responsive to that, her water input and urine output are extreme. Lastly, she has begun to really gain weight recently and lose hair. Can you offer any advice about the hair loss? My guess is that the weight gain is related to too much insulin, but the hair loss has me baffled. And, any advice (other than ear sticks at home - we don't want to do that to her) you can give us about regulating her?

Thanks. Helen

Answer: Helen-

It sounds to me like you are probably doing OK at this time. The most realistic goal for insulin therapy is to keep the blood glucose level in the recommended range for about 20 hours of the day. The odds seem pretty good that you are achieving this level of control if you are only getting high glucose sample in the urine just prior to the insulin injections.

Depending on what you are already doing and what is practical for you to do, there are some things that do help to control swings in blood glucose levels. Some cats require different levels of insulin in the two injections when using twice daily insulin. We have a patient that does best on three units in the morning and two at night, for instance. Other patients do better if insulin is given three times a day, but that is pushing the limits of practicality for many people. Other cats do better if a fast acting insulin (like regular insulin) is mixed with the longer acting NPH insulin so that the there is a quick effect and then a slower effect. Sometimes, feeding four times a day instead of three times a day will help -- although most of our diabetic cat patients have food available all day.

Doing a glucose curve to see exactly what is happening is the best thing to do. You don't have to do them too often if you have a good idea of what works for you and your cat, but checking every now and then is still a really good idea. We do "mini" curves where we only check the blood from 8AM to 5PM and most of the time this gives us sufficient information to successfully adjust insulin dosages.

Weight gain sometimes accompanies good regulation of insulin levels.

I can't help much with the hair loss except to point out one possible complicating factor that would explain the difficulty in regulating her insulin and the hair loss, which would be hyperadrenocorticism. This is not a common problem in cats but it is more common in diabetic cats than in the general cat population and it is a cause of difficulty regulating insulin levels. Actually, I can think of two problems --- acromegaly might also cause both problems, although hair loss is not commonly listed as a sign with it, either. It is definitely a complicating factor in cats as far as insulin resistance goes, though. It can be a little hard to definitively test for these conditions in cats but your vet can give you an estimation of their likelihood based on a physical exam, checking for current signs of insulin resistance with a glucose curve and through lab testing.

At this point, a recheck with your vet is probably the first step. You might want to ask about the possibility of a secondary problem like hyperadrenocorticism (Cushing's disease) or acromegaly, if your vet doesn't discuss them with you.

Good luck with this.

Mike Richards, DVM 9/26/2000

Possible Diabetic mimics - Acromegaly and Hyperadrenocorticism in cats

Question: Hope all goes well with you! Days are passing faster than the human mind can comprehend here, but with "God willin' and the creek don't rise", we're getting thru them one at a time!

Many thanks, as always, for the monthly newsletter. It is still the highlight of my month!

Two questions, please?

Could you tell me, in general, what feline disorders would mimic diabetes exactly except the massive weight loss is major weight gain? and What readings on a full blood, chem, and T3 & T4 test would be indicative to the disorder?

With Gratitude, Lyn

Answer: Lyn-

I don't think that I know of a disease that mimics diabetes exactly except produces weight gain. However, acromegaly sometimes causes symptoms similar to diabetes and is sometimes a complicating factor in diabetes. Hyperadrenocorticism can have most of the signs of diabetes, especially the increase in drinking and urinating. This is not a common problem in cats but it does occur.

Acromegaly is a disorder in which excessive growth hormone is produced. It produces many of the signs of diabetes, such as haircoat changes, exercise intolerance and increased drinking and urinating (polyuria/polydipsia or PU/PD). In this case the PU/PD behavior usually occurs due to insulin resistance that eventually does lead to actual diabetes mellitus as a complication of the acromegaly. It would be unusual, in a cat, to detect this condition prior to the time that diabetes was already present. It is possible to measure growth hormone, but it is usually reasonable to diagnose acromegaly in a cat when there is an increase in blood sugar, signs of bone growth such as widening of the gaps between the teeth, increase in the size of the head or face, heart murmur, long thick hair coat or some combination of these signs and there is no evidence of hyperadrenocorticism or hyperthyroidism.

Hyperadrenocorticism (HAC, Cushing's disease) is a disorder in which there is excessive production of cortisol, as the result of pituitary gland disorders (hypertrophy, cancer) or adrenal gland cancer. This can be hard to confirm in cats but the current thinking is that low dose dexamethasone testing is the best test for detecting hyperadrenocorticism in cats but it sometimes has to be done twice, once at the usual low dose and once with a higher dosage of dexamethasone since up to 20% of cats with hyperadrenocorticism won't have the suppression in cortisol levels that the test normally causes at the lower dosage. Cats do not have much change in serum chemistry values when they have HAC, except that many cats with this condition do have increased sugar levels or diabetes and sometimes cholesterol or alanine transferase (ALT ) may be high, as well.

There are probably some other possibilities but these are the two that I can think of.

Mike Richards, DVM 8/21/2000

New symptoms in diabetic cat

Question: Dr. Mike: Am confused on this one. I usually can piece everything together, but it can't seem to get a handle on it this time. Can you explain: Bear with me, this all ties in, somehow.

Every since Jake came off the "honeymoon", I've been able to keep his glucose level between 120-175 with 1 to 2u of PZI 2bid. I do his glucose test every 7 days & more often if symptoms occur in between. They've always been the normal increase in drinking AND eating at the same time.

During the past week, I've had to take him up from 1 to 4u 2bid. I won't know until Sunday morning's reading if the 8 is working. The readings were at 104-110 & shot up to 408.

Regular Maintenance things I do:

1) With his PM dose I give him a Vitamin supplement called Cataplex GTF (order this thru a vet in Colorado) crushed & mixed in 3cc of liquid aloe formulated for stomach ailments (again all natural ingredients.) We've been doing this for 4 years & I've proven 4 times that it is critical to his levels & temperament. I've he's off it more than 5 days, the sugar goes sky hi & he becomes extremely aggressive (even attacking me if I try to break up his skirmishes with his brother). During these spiking episodes, I give it to him with both shots.

2) Both he and his brother have severe constipation problems, so every 6 weeks or so, I grate raw carrots & mix it in their meals for a week. It work & there has been no significant change in Jake's glucose levels.

This time the sugar levels soared about 4 days into the carrot mix. Too much natural sugar in the carrots this time?

3) For the same reason, roughly 1x week, I mix a high-fiber powder named BoodaMix 10 into their canned food. It's all natural ingredients (a few surprise me: diatomaceous earth & montmorillonite clay). Same response as No. 1.

4) This is a first-timer, but the problem started before it: I picked up a bag of Iams Hairball Remedy dry food. They love it - unbelievably so. They've even stopped bugging me for their wet food which was a 5x daily thing.


1) He's increased his water intake by at least 60% AND decreased the food intake by about 40%. He's voiding what I estimate to be 90% of what he's drinking & "pooping" better than he has in months.

2) He's taken to sleeping on the kitchen floor - an ABSOLUTE FIRST.

3) He gets just a tad more disorientated from time to time.

His sleep habits remain normal, I do an "alert check" regularly & he responds well, his coat remains silky (it always turns greasy when his levels go up), he has no apparent signs of fever, his hind quarter started to stiffen up about a year ago & he walks like a penguin, but that doesn't seem to be any worse, and he also started to loose his balance a little when he shakes his head, but that doesn't seem to be any worse either.

I really don't want to know where this is leading to, but I have to.

Your thoughts, please. My Best Regards, Lyn

Answer: Lynn I think that there are six problems mentioned in your note -- loss of control of blood glucose regulation, stiffness of the rear legs, loss of balance, constipation, decreased appetite and behavioral changes. Of these problems, stiffness of the rear limbs, loss of balance and constipation are long standing problems. The loss of control of the blood glucose level and behavioral changes (sleeping on the kitchen floor) are new.

The list of differentials for these conditions (at least the ones I can think of) are as follows:

stiffness of the rear limbs: degenerative joint disease (arthritis) low blood potassium diabetic neuropathy myositis, polymyositis polyneuropathy spinal disc problems feline polioencephalomyelitis

constipation: megacolon inflammatory bowel disease colitis

loss of balance: toxoplasmosis brain tumors inner ear disease high or low blood sugar levels liver disease causing encephalopathy feline infectious peritonitis (FIP) feline polioencephalomyelitis

decreased appetite: inflammatory bowel disease low or high blood glucose systemic illness (liver, kidney, heart disease) hypophosphatemia (low phosphorous levels in the blood) hypokalemia (low potassium levels in the blood) hyperthyroidism, in a small number of cases pancreatitis

difficulty regulating insulin: improper administration or handling of insulin hyperadrenocorticism acromegaly insulin resistance interference from other medications (especially cortisones)

infections (bacterial cystitis is common in diabetics)

behavioral changes: hyperthyroidism brain tumors hormonal illnesses

pain inability to jump as well as in the past may be causing the new tendency to sleep on the floor.

These are some things to think about. PZI insulin as it is currently available, through compounding, has a reputation for being inconsistent in its effect, making regulation with it difficult at times. I am not sure that this is a problem with the source of PZI insulin you have, but I think you have to keep this problem in mind, as a potential cause of the current problems. I would worry about this more if you recently got a new bottle of insulin or if it is taking a long time to go through a bottle of insulin.

We have had several clients who are very happy with the hairball food from Science Diet. It seems to help cats with constipation, regardless of the cause. I do not know what its effect on diabetes regulation might be.

I would tend to worry about the hormonal illnesses first since they can cause the majority of the problems you are seeing. Hyperthyroidism commonly complicates insulin regulation, hyperadrenocorticism is less common but does sometimes cause problems with insulin regulation and acromegaly is uncommon but really screws up insulin regulation.

It is always a good idea to think about bacterial infections of the bladder (cystitis) as a complication in cats with diabetes.

There are times when it is best to seek the help of an internal medicine specialist with an interest in endocrinology. If it is not possible to get some regulation of the insulin soon, that would be a good thing to consider.

Hope this helps some.

Mike Richards, DVM 5/13/2000

Bowel problem in diabetic cat

Q: Dr. Mike, Calico measured about 230 on glucose tests last week, Thurs, Fri, Sat. However she hadn't eaten since the Tues before the Thurs, and had thrown up all Wed am. She last had glucose last Wed am before throwing up. On Mon my regular vet had a sub who anethesized her, and manipulated her for about a half hour , with enema. Nothing passed , nor that night. He was so negative about her, that on Tues I went to a different vet. This vet was successful at removing most of it. He kept her all night. Reported that she ate and peed. But no bm Wed pm I picked her up. Since home, she had done little peeing and no bm. She is straining again. The last vet and the regular vet were worried about mega colon. (I don't yet know what it was, since they said it in passing, and there was so much going on I didn't follow up on it). I fear she has lost elasticity ... (maybe this is mega colon). She is on wd with vetasyl. The last vet, Dr. M. also thought she was low on potassium, and she is on Tumil-K.

Now Dr. M is out of town til Mon, he has a sub, but I don't want to deal with another new person on this. The sub to my regular vet mentionned Metamucil. What do you think of this? It seems like I need to get her feces very loose to get her colon back to operation ... Any ideas? What about lactulose and cisapride? She is off insulin for now. Thank you.

A: Jill-

I think that it is worth considering cisapride (Propulsid Rx), based on the information available on it. Many vets have had good success with it. We have been very lucky in our practice and have been able to control most cases of constipation with either lactulose or metamucil type products (same basic ingredients as Vetsyl -- so no advantage I know of to switching). If the constipation is treated early and consistently, many cats seem to avoid developing the large colons that can't contract well that typify megacolon in cats. It is definitely worth being somewhat aggressive in therapy for this condition, if that is what it takes. It is safe to supplement oral potassium within the usual dosing guidelines, even if she doesn't need it. And it can be beneficial in helping with muscle contractility, so if it is low there is good reason to supplement it.

I am very worried about the fact that she is off insulin. Unless she didn't need it, which should be apparent pretty quickly if blood or urine sugar values are monitored, then it is also an important medication for the prevention of megacolon. Everything in the body, just about, requires sugar and the only way to get it into cells properly is with adequate insulin.

Please do check with your regular vet in the morning (Monday) and keep in working at this. I really think you have a good chance of warding off the worst possibilities if you keep working with your vet to resolve these problems.

Good luck with this.

Mike Richards, DVM 8/10/99

Diabetes, insulin and neuropathy

Q: Hi. My cat has diabetes, is not responding well to Humulin Ultralente. Will be switching to Lente very soon. The neuropathy is very serious, in all her legs. She cannot jump, and walks with difficulty. 1. Is this neuropathy reversible? What is it exactly. It seems to me that due to the large volume of urine she must be losing all the water soluble vitamins. She started on some vitamin pills last week Vet a Mix. 2. Do you think this neuropathy might be due to vitamin and mineral deficiency? 3. Where might I get PZI? My vet used to use it and is familiar with it.

A: Jill-

PZI insulin was briefly off the market again, recently. However, a new manufacturer is currently making it, although it is not fully FDA approved. It can be ordered on an experimental basis with the proper forms. To order PZI insulin, your vet should call Blue Ridge Pharmaceuticals at 1-800-374-8006.

If your vet has had previo


Michael Richards, D.V.M. co-owns a small animal general veterinary practice in rural tidewater Virginia. Dr. Richards graduated from Iowa State University's College of Veterinary Medicine in 1979, and has been in private practice ever since. Dr. Richards has been the director of the PetCare Forum...