Side Effects of Steroids in Pets

Eirevet is a veterinarian specialized in canine and feline internal medicine
who owns a small animal veterinary hospital in Ireland.

Are Steroids Safe For Pets?

Corticosteroid medications such as prednisolone ( prednisone) are
widely used in both human and veterinary medicine to treat allergies, cancers,
and autoimmune issues such as atopic skin disease, flea allergy, inflammatory
bowel disease, and rheumatoid arthritis, to name but a few. Used
appropriately, steroids can greatly improve your pet’s quality of life while
helping to treat serious illnesses.

Unfortunately, steroids are often not used appropriately, either due to
incorrect or incomplete diagnoses or due to owners’ lack of understanding of
the potential side effects of medications such as prednisone.

The following discussion aims to inform readers of these side effects and
suggest possible methods to reduce steroid use in some specific conditions.

Common Side Effects

Corticosteroids are produced naturally in the adrenal glands and have a number
of important functions in a healthy pet. Cortisol, the predominant naturally
occurring steroid, has

anti-inflammatory functions
homeostatic functions
immune-modulating functions

These beneficial effects are dependent on the proper functioning of feedback
mechanisms between the adrenal glands, pituitary gland, and hypothalamus. The
low levels of endogenous steroids are constantly fine-tuned by communication
between these organs. When communication breaks down, an animal may develop
serious problems such as Cushing’s Syndrome or Addison’s Disease.

When we administer corticosteroids in the form of prednisolone or prednisone,
we override this sophisticated feedback mechanism and are likely to cause at
least some mild symptoms of Cushing’s Syndrome. These signs are discussed
below.

Behavioral Changes

Effects of prednisone vary from one animal to the next, and while some pets
will become agitated, hyperactive, or even aggressive, it is most common for
owners to notice lethargy and reduced energy levels. While some of this effect
seems to be due to a direct effect on the brain, exercise intolerance because
of muscular and respiratory effects are likely to also play an important role.

Yorkshire Terrier with naturally occurring Cushing’s Syndrome

Steroids Cause Increased Thirst and Urination

Corticosteroids have a massive impact on the body’s ability to conserve water,
increasing fluid loss through urination by several mechanisms. Increased
levels of glucose in urine draw out water through the kidneys, while
mineralocorticoid effects alter electrolyte levels, driving thirst and
increasing excretion.

For these reasons, it is very common to notice an increase in water intake,
and it is also possible that your well-trained indoor dog may start leaving
puddles of urine in the house due to an increased frequency of urination
coupled with weaker control of the bladder sphincter muscles.

Steroid Medications Make Your Dog Hungry

As mentioned above, a pet receiving steroids will experience mild-to-moderate
diabetes symptoms. By reducing the effects of insulin in the body, prednisone
will increase blood glucose levels, while reducing the body’s uptake of
nutrients (in lean tissues) and creating a feeling of hunger.

Unfortunately, corticosteroids also encourage the deposition of fat, so while
pets with true diabetes will lose weight, those on prednisone and prednisolone
will actually gain weight in the form of fat, while losing muscle mass.

Swollen, pot-bellied appearance of a dog on steroid treatment

Steroids Cause Muscle Wastage

As alluded to above, dogs on steroid treatment will exhibit marked muscle
wastage. This is often most evident in the temporal muscles, giving the face
and forehead a ‘sharper’ appearance. Loss of muscle strength in the abdominal
wall leads to a characteristic pot-bellied appearance (as above), and muscle
loss in the limbs contributes to exercise intolerance.

Scroll to Continue

Why Does My Cat Sit on My Stuff?

Tips for Home Care for Your Vomiting Cat When You Cannot Visit the Vet

The Top 10 Fastest Dog Breeds

Another common complaint from owners is that their pets pant excessively; this
again is due to muscle weakness in the chest wall and diaphragm, while house-
soiling is at least partly due to effects on the sphincter muscles.

A rare complication of treatment is corticosteroid myopathy , which is a
very painful condition due to depletion of intracellular levels of carnitine
in skeletal muscle. If identified early, this can usually be rectified by a
reduction of dose and initiation of carnitine supplementation.

Skin thinning and loss of elasticity due to steroid treatment

Side Effects on Skin and Hair

Although prednisone (prednisolone) is most often prescribed for skin disease,
high doses can cause undesirable effects on coat and skin quality. Comedones
(blackheads) are commonly seen, while skin thinning and fragility can cause
striae (stretch mark) formation or even skin tearing in severe cases.

Calcinosis cutis, the deposition of calcium within the skin, can occur with
very high doses, and can cause unsightly hard lumps to develop, often erupting
through the skin surface.

Hair loss and a failure of hair to regrow following clipping are also
extremely common effects.

Steroids Cause Immune Suppression

As well as causing the death of certain white blood cells (lymphocytes),
corticosteroids inhibit communication between the components of the immune
system, making unwanted bacterial infections a common complication of
treatment.

Dental and urinary tract infections are most commonly seen, and any pet
receiving long-term steroid medication should have regular oral examinations
to detect the early stages of periodontal disease and hence prevent tooth
loss. Regular monitoring of the pet’s urine is also recommended to detect
urinary tract disease, which often exists without obvious signs.

Less Common Side Effects of Steroids

System| Dog| Cat
—|—|—

Cardiac

–

Can cause myocardial thickening (rare)

Liver & Pancreas

Hepatic lipidosis, pancreatitis

Gastrointestinal

Vomiting, diarrhea, ulceration

Bloodstream

Blood clots / stroke

Reducing the Need for Steroid Medication

The key to reducing all of these unwanted side effects is to reduce the dose
of steroid being administered. Your veterinarian should be advocating
complementary therapies for your pet’s primary problem in order to achieve
this. These other therapies will vary depending on the specific problem being
treated.

Almost all pets with autoimmune or allergic problems will benefit from Omega 3
fish oil supplementation (see above). These oils are powerful anti-
inflammatories and provide some protection from adverse steroid effects.

When dealing with allergic skin disease, it is crucial that any concurrent
bacterial and fungal infections are controlled with appropriate topical and
systemic treatments. Malaseb is a very useful shampoo when managing the
first presentation of skin disease or when skin flares up, while a protectant
shampoo such as Allermyl should be used for maintenance washing.

Pets with digestive problems will usually benefit from dietary change,
meticulous parasite control, probiotic treatments, and low-dose antibiotic
treatment. While steroids will usually still be required, the dose will often
be greatly reduced.

Finally, one should be aware that steroids need not be used in isolation for
treating any of these ailments. While prednisone and prednisolone will usually
be the first-line treatments, other drugs such as oclacitinib, ciclosporine
and azathioprine can often be used in combination to reduce side effects.

As a veterinarian, I can say without a doubt that countless animals would lead
poorer lives without the availability of steroid medication for the treatment
of many common conditions. However, there is much scope on the parts of both
veterinary surgeons and owners to exercise greater care in their use and to
explore alternative treatment options in order to minimise potentially harmful
side effects.

Supplements for Pets on Steroid Treatment

Survey

This article is accurate and true to the best of the author’s knowledge. It
is not meant to substitute for diagnosis, prognosis, treatment, prescription,
or formal and individualized advice from a veterinary medical professional.
Animals exhibiting signs and symptoms of distress should be seen by a
veterinarian immediately.

Please Share Your Experiences of Steroid Treatments

Jane Dumic on April 23, 2019:

My dig was on steroids because of mms, she was weaned off but I’m strugling to
reduce her weight. She does not eat much but seems to be obese.

Addie W on December 17, 2017:

My dog has been diagnosed with ITP a month or so ago. Been on Pred 20 twice a
day and Atopica. Now they say her blood work looks good except elevated liver.

Is the Pred or Atopica the cause? And how should I taper back? She was
critical at onset I spent thousands saving her. I put my family in financial
crisis. I cant afford continued vet apt. To tell me more tests if it is that I
shoued ween off drugs. And the Atopica is very expensive! So which one is it
doc? Pred. Or Atopica causing this? Right now we had decided to ween off I
wanna know how to do it… and to pay close attention to her reactions, and go
for blood work every few weeks..

So pls tell me how to ween off. From reading I think Omega 3 should be
introduced to replace pred, and melatonin for platelet support. Pls advises
asap.

My primary vet that referred us to internal medicine kinda leaves it up to
them and I am not impressed. They tell me to get blood test for dog there and
they will get results and then they tell me they want a follow up with the dog
and then do the same blood wk and additional procedures its too much!
Emotionally draining. Financially killing. Her liver and everything was fine
until the meds and I told the dr. I had learned one of these meds could effect
liver and she was like oh no hasn’t been seen and here we are!! Only thing
noticeable is her whites of her eyes are a little dirty not yellow. She hasn’t
gotten pot belly or crazy eating. Drinking yes, appetite good, muscle loss
around head yes. Happy wagging tail yes and little skip in her step yes.. She
is 10 Please help. I know I can do this! With some proper outside advice..

Janice Kay on September 27, 2017:

Causing skin issues and fatigue. Wish I could find something for colitis
besides steroids.