Medication - Prednisone and other Corticosteroids


Glucocorticoids, including prednisone and gastric problems

Question: Dr. Richards:

My male (n) husky is 12 y/o. He has bad hips and a CNS problem, most likely spinal stenosis. His outlook on life is still great.

The immediate problem is maintaining his weight. He has never been much of an eater. Two months ago we put him on steroids (pred at 20 mg per day). He also receives adequan injections weekly and daily doses of cosequin.

The pred seemed to stimulate his appetite (nothing great, but at least he was eating something at every meal) until 3 to 4 days ago. Now he is back to a mouthful of food and a couple of biscuits a day.

He is seen weekly by my vet and there are no other known problems that explain his food aversion. Someone suggested that pred over time can cause stomach irritation, even ulcers. Is this true? Is this documented in the literature?


Answer: Palmer-

Prednisone and other corticosteroids have a lot of different effects on the digestive tract.

It is well documented that glucocorticoids, including prednisone, increase the risk of gastric ulcers. This happens due to a combination of effects of the corticosteroids. The stomach produces a protective mucous layer that helps it defend itself against the acid it produces. Corticosteroids interfere with production of this mucous layer because they suppress the growth of the gastric mucin cells that produce the mucous. In addition, corticosteroids inhibit the production of mucous in the cells that remain. Eventually, this leads to a thinning of the protective layer and a greater risk of ulcer. The rate of ulceration has not been established in dogs, at least that I know of, but it is about 5% in humans with long term use of corticosteroids. This may be a little higher than in animals because people probably have an increased susceptibility to Helicobacter infections while on prednisone and the role of Helicobacter in dog and cat ulcers is still unclear.

Long term prednisone use also decreases the absorption of minerals (especially calcium and iron) from the digestive tract and increases the absorption of fat. It may increase the risk of pancreatitis. On the plus side, glucocorticoids decrease inflammation, which can be very beneficial in some gastrointestinal disorders, such as lymphocytic/plasmacytic enteritis and they may offer some protection against stress related ulcers.

It is best, whenever possible, to use prednisone on an every other day basis when it must be used long term. There are situations, including some of the spinal diseases, in which this isn't possible if a beneficial effect is to be maintained. In these cases it is sometimes really hard to figure out how to handle the negative side effects. At least for the ulcers some protection can be gained by using cimetidine (Tagamet tm), famotidine (Pepcid AC tm) or other gastrointestinal protectant medications.

It might be worth trying carprofen (Rimadyl Rx) or etodolac (Etogesic Rx), if this hasn't been tried. Sometimes the additional pain relief gained with these products makes up for the fact that they aren't quite as powerful anti-inflammatory agents as the corticosteroids.

I hope that your husky is feeling better at this time but if he isn't, you might ask your vet about using something like cimetidine or famotidine or trying to find an alternative to corticosteroid usage, although this might not be possible.

Mike Richards, DVM 9/9/2001

Long term Prednisone use in Rottie

Question: Hello! My old Rottie is 10 years old and recently he started to have problems with his rear legs and the veterinarian put him on Prednisone 20mg for 21 days lowering the doses as the treatment finishes, when he finished the treatment he started to get worse than before the treatment, he started to lose his balance from the left upper leg and began to fall, so the doctor put him on Rimadyl up to now I don't notice any positive response on my dog up to a point that he couldn't even get up by himself. So again I visited him and do a SMA blood test and urine test, the blood test was good but the urine test demonstrated that the creatinine is high, the urine is not concentrated but the Phophorus is good, so he change the food to Hill's Prescription Diet K/D. All of a sudden he began to fall but the problem now is on his right rear leg and is thirsty at all times and don't urinate like he was before and his abdomen is getting bigger (like if he had ascites) specially at night time, so I gave him Lasix and stop the Rimadyl and he started to urinate. I don't notice any change with or without the Rimadyl for these last five days. Some days ago I noticed than when he was drinking water he started to cough, so I called the doctor and he checked my dog, now he prescribed again Prednisone 20mg for 14 days because he think the dog has some neurologic problems and that's why he falls. Personally I don't like the idea of putting him on cortisone again, Can Prednisone harm any organ system of my dog? Is there some drugs to treat neurologic problems in dogs like in humans? Does his doctor is giving a good approach to the problem?, please give me your opinion or if there is any other drug that I can use in my dog? I am afraid that the Prednisone had damaged his kidneys and if I started it again it could damage any other organ. Thanks for helping me and my dog. Vilmarie

Answer: Vilmarie-

It usually takes very long term use of prednisone or other corticosteroid medications before side effects that might lead to kidney damage occur. If prednisone is helpful for your rottweiler's problem it is probably best to go ahead and use it as your vet advises.

There are several things that could cause the symptoms that you are seeing in a rottweiler. The abdominal enlargement is worrisome, as this is often associated with cancers, such as hemangiosarcoma when seen in large breed dogs who do not have liver failure or heart failure. The weakness in the rear legs could be due to disc problems in the spine, lumbo-sacral instability (pretty common in large breed dogs), bilateral rupture of the cruciate ligaments, bone cancer (unfortunately a fairly common problem in rotties) and probably some other things that are not coming to mind right now. Central nervous system problems, especially vestibular disease, could lead to difficulty walking. Inner ear infections can cause balance problems, as well. There are treatments for several of these conditions, but not for all of them.

In this situation, the best thing to do is to continue to look for a diagnosis. X-rays of the spine, abdomen, hips and perhaps the stifles may be helpful in making a diagnosis. If there is fluid in the abdomen, analysis of the fluid could give a good indication for why it is there. Blood values may change rapidly, especially if hemangiosarcoma is present, so repeated lab work may also be helpful. In some case, more sophisticated imaging techniques, such as MRI or CT scans may be necessary to find spinal or brain problems. Ultrasound imaging can be useful if there is abdominal fluid accumulation since it is better "seeing" through the fluid than X-rays and because tumors in the spleen or liver are more easily visualized with this type of scan.

I am hoping that things have improved, rather than getting worse. Please keep working with your vet to try to find the cause of your rottie's problems so that they may be treated most effectively.

Mike Richards, DVM 1/26/2001

Corticosteriod side effects

Q: What are the side effects of Corticosteriods?

A: Carol-

Corticosteroids occur naturally in both dogs and cats. They are produced by the adrenal gland. They have effects on most of the body's systems. For this reason, using them therapeutically tends to produce a lot of side effects.

Cats are more resistant than dogs to the effects (and side-effects) of corticosteroids.

The most common side effects associated with the use of corticosteroids are increased drinking, urinating and appetite. These effects are less noticeable in cats than dogs but weight gain does seem to accompany the use of corticosteorids in cats pretty frequently.

Prednisone and other corticosteroids may cause other side effects, as well. Hairloss, dullness or thinning of the haircoat is occasionally seen in cats. Thinning of the skin and increased susceptibility to skin infections may occur. Panting is commonly seen in dogs as a side effect of corticosteroid use and is seen less frequently in cats, as well. We have had a couple of feline patients who developed diarrhea as a side effect of prednisone usage. Ulcers are reported to occur sometimes after corticosteroid usage but I don't recall seeing this problem in any of our patients.

Generalized immune suppression can occur, particularly at higher corticosteroid doses or with frequent administration of corticosteroids. This is the side effect that we worry the most about in cats, as there is some evidence that corticosteroids can make it possible for dormant feline leukemia virus or herpes virus infections to reappear. It is a good idea to watch carefully for signs of illness when it is necessary to use corticosteroids in a cat and to report any signs of illness to your vet as soon as possible.

Corticosteroid may lead to an increased incidence of pancreatitis in dogs but I am not sure if this problem occurs in cats. Use of cortisones makes it harder to control insulin dosages in diabetic pets and they may even help to induce diabetes in susceptible pets.

In people, corticosteroid induced pyschoses are reported. I honestly think that this occasionally occurs in pets but have no real scientific data to support that belief. Still, if your cat starts hiding out all day, is more aggressive, or exhibits any recognizable behavioral changes it would be worthwhile to report them to your vet.

There are probably other side effects that I haven't thought of. Sometimes when I look at the lists of things that corticosteroids do that aren't good for the patient it is hard to understand why we use them. But it is important to remember that they also have beneficial effects, as you have seen. As long as the beneficial effects are important and are providing an increased quality of life it seems reasonable to use corticosteroids. You just have to be careful to watch out for the pitfalls and adjust treatment plans accordingly.

Hope this helps.

Mike Richards, DVM 5/20/99

Behavior changes and Prednisone

Q: Dear Dr Mike, We Have a four year old male, neutered border collie that has eosinophil colitis. He has been on prednisone for the last three years. ... he started at 20 mg per day for several weeks then was on 5mg per day for well over a year and is now at a maintenance level of 5mg every four days. Over the last 6 months, the dog has begun to get fearful of things and also has begun to growl and snarl at anyone who touches his face. He now spends most of his time hiding in our bedroom and is afraid to go outside at night. This was a very obedient and loving animal a year ago and now does not want anyone around him. There is not metabolic damage caused by the prednisone but could this drug have damaged his brain? We are currently trying to contact a behaviouralist. Is there anything else you can suggest? Thanks for any assistance in this matter. Mike

A: Mike- Corticosteroids are known to cause psychological problems in people. I am not sure of the incidence but it occurs. I have always assumed the same was probably true for dogs. I had a Lab mix dog whose behavior almost exactly matched your dog's when she was on prednisone. She had really severe allergies and didn't respond very well to hyposensitization so we just tried to use the absolute minimum amount of prednisone necessary to control the itching when it got so severe that antihistamines, fatty acid supplements, bathing and keeping her in the airconditioning all weren't enough.

Mike Richards, DVM

Corticosteroids for allergy

Q: Dear Dr Mike, I have an 8 year old male German Spitz cross breed. Last Thursday, 27 June, I took him to a vet to treat him for a slight skin allergy under his legs. The rash had almost dried up but the vet gave him an anti-inflammatory injection which later we found out had a low dose steroid (0.48%). On Monday, 30 June I noticed he was drinking lot more water than usual and waking me up many times through the night to be let out to urinate. Yesterday, 2 July we took him to the vet again and this time his associate who was on duty told us that it may be a reaction to the steroid but it sounded like too strong a reaction. She took a urine sample and although extremely diluted found no signs of diabetes. She then took a blood sample and the results came back yesterday evening. It told her that his kidney was healthy but 2 enzymes in his liver shows abnormal values. The ALP count was 122 and the ALT count was 858 which was more of worry. She told me that since he was alert and looked healthy I should wait another week to see if his symptoms of drinking too much water, constantly hungry and urinating more often and for longer periods persist She said maybe the injection is the cause and she would like to take another blood sample next Wednesday to do the count. Is it common to treat mild contact dermatitis with steroids? Do steroids normally cause these reactions? Is it possible his liver has been damaged permanently from this injection? Any comments would be much appreciated. I do so love this little guy. Thanks.

A: Joanne- It is not unusual for veterinarians to use corticosteroids for allergic reactions. I can not tell which one was used from the history you give but it is also not all that unusual for corticosteroids to cause increased urinating and drinking -- even marked increases with some injectable products. This usually doesn't last more than a few days after the injection and it should definitely have stopped by now. Corticosteroids will often induce rises in liver enzymes. This rise is a reaction to the medication and usually does not indicate liver damage. It does seem like it would be a good idea to try to utilize other treatment methods in the future, if they will work.

Mike Richards, DVM


Q: Dr. Mike: We have a 15 year old shepherd/hound cross, who still seems happy enough with life. He is on Prednisone (prescribed at 2 5mg tablets, every other day) for pain and inflammation (arthritis). He had also lost weight as he went from 85 lbs down to 70 lbs, where it has now stabilized. This seems a good weight as he has lost muscle - and his appetite has recovered and is now satisfactory. To simplify matters we actually gave Smokey 1 tablet every day for about a month, until the prescription needed refilling. The veterinarian indicated that the reason for the "two and none" regimen was to give the dog's endocrine system a chance to recover. We pointed out that the dog was 15 and that it appeared to us that his future life span was limited in any event. The vet then said he understood the point and that perhaps it really didn't make that much difference, but he preferred "two and none". We then gave Smokey the "two and none" for about a week, but his condition seemed to go up and down. Also, we managed to forget the pills a couple of times until later in the day .. and we can only see this happening more frequently (we're old, too .. 70!). Our question is: given the dog's age, is there a really strong reason for the "two and none", or will "one a day" be satisfactory? Thanks for the opportunity to pose a question, and for your time. This is a great site. Russ

A: Russ-

Your vet has summed up the situation with prednisone pretty well. Your dog's body can not really tell the difference between types of cortisones and if a sufficient quantity of cortisone is in the body, the endocrine system suppresses cortisone production by the adrenal glands. The amount of cortisone administered orally as prednisone is almost always well in excess of what the dog's body would produce naturally. So giving it daily suppresses the adrenal glands. Over time, this suppression causes the gland to have a difficult time making cortisone when a sudden demand is placed on it. This is a problem when cortisone is withdrawn rapidly and can even result in the death of the dog. If the cortisone is never withdrawn this effect is not as worrisome but it is very important to keep it in mind.

High levels of cortisone in the body produce several other problems over time. Skin damage can occur, resulting in skin sores known as calcinosis cutis, thinning of the skin and hairloss. Suppression of the immune system occurs, making bacterial infections more likely. Increased drinking and urination can become a problem. Muscular weakness can occur. Pancreatitis is more common in dogs on long term cortisone therapy. These side effects are minimized but not completely eliminated by every other day use of prednisone. In any situation in which long term use of prednisone is anticipated, these things must be considered as possible side effects. These effects are probably more important than the adrenal suppression in most patients.

Despite all of this, I will use prednisone on a daily basis when it is the best medication for older dogs with arthritis, especially when they are at or near the point where the owners would consider euthanasia without the benefits of the medication. My reasoning in this instance is that side effects may take a long time to develop into a problem and any time past the time euthanasia is being considered is better than none. Now that carprofen (Rimadyl Rx) is available there is an alternative to prednisone for some patients and we are making this decision a little less often than in the past.

Ultimately, you have to decide what is best in this situation since you are in the best position to judge the importance of using the medication every day. Your vet is correct that alternate day dosing is best in most circumstances but there are times when it is appropriate to make exceptions. Mike Richards, DVM

Prednisone and diabetes

Q: Hello, I have two separate questions.

1) The first question is have you seen any reports or studies that indicate an association between the use of predisone in dogs or cats and the onset of diabetes?

A: C- It is pretty widely accepted that prednisone may predispose dogs and cats to diabetes. It is not as clear to me whether this is enhancement of an existing tendency to develop the disease or if it is an independent effect. They also can induce insulin resistance, leading to hyperglycemia. In diabetic patients, corticosteroids can make insulin regulation more difficult since they have this effect on blood sugar levels. I think this is a relatively rare side effect but it is a consideration, especially in a pet likely to already be predisposed to diabetes.

Mike Richards, DVM

Prednisone & Chow Chow

Q: My Chow Chow is 5 years old and has been taking Prednisone for about 3 1/2 to 4 years now. Lately he seems to be hallucinating as if bugs were crawling on the ground or flying in the room. I started giving him Pred when he was about 1 year because he was getting fidgity and breathing heavy and scratching so badly that he got bloodly hot spots on his hind end and on his stomache. The vet prescribed Pred and all his symptoms went away and he was playful and happy and his fur was beautiful. After the pills ran out (about 1 month supply of 20mg 1/2 pill every other day) it took about 3 months and he started getting fidgity, scratching & his fur started falling I took him to the vet and got a refill and so on for 3 more years. Now he just seems to be different. The vet I just went to said, as long as he is happy and doing well the pills are okay. He didn't know what kind of side-effects they caused or if it shortened the dogs life. But, like I said, just lately he's been acting strangely...not all the time, but sometimes. I love this dog sooo much, and I just want to know what to expect from his long-term taking of this pill. Please get back to me, as I as very concerned. Thank you...and this is the first time I've gotten into the net for this help. Your credits sound very reputible.

A: Prednisone is known to produce a "steroid psychosis" in some people. To the best of my knowledge, no one really knows for sure if this occurs in dogs, but I believe that it does. I have seen two or three dogs with really strange behavior when they were on prednisone that cleared up consistently when they were not on prednisone.

Allergies are also reported to produce central nervous system effects, including behavioral changes, in some dogs. This always makes it hard to decide if the problem is from allergies or from the treatment of the allergies.

Another thing I would consider in your dog's case is a visual problem. Sometimes the "fly biting" behaviors are actually due to visual problems which make the dog see motion or flashes of light that are not actually present. Retinal damage and "floaters" in the posterior chamber of the eye can have this effect.

Lastly, this could be seizure activity. Some dogs appear to have psychomotor seizures and that could be the problem.

If prednisone does control all of the symptoms then I think I would recommend staying with it in most cases, too. As long as it is used every other day or less, it is reasonably safe. The increase in comfort for a pet is worth the small risk associated with use of these medications when they are helping. If prednisone is not controlling these symptoms, I think I'd be wanting to refer your dog to a specialist -- or preferably to a vet school or large referral center where they had several specialists. A dermatologist, an ophthalmologist and a neurologist, just in case.

Corticosteroids like prednisone probably do not shorten the lifespan when used judiciously. They do have several side effects, including lowering the immune response, increasing drinking, urinating and appetite and predisposing dogs to diabetes and possibly pancreatitis. Again, using prednisone every other day makes all of the side effects less likely to occur.

Good luck with sorting this all out. Mike Richards, DVM


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...