Prednisolone is a synthetic glucocorticoid steroid commonly used in cats as an anti-inflammatory or as a treatment for immune-mediated conditions. In this article you’ll learn what prednisolone is, some conditions it may be used for in cats, and side effects to look out for.
What Is A Steroid?
A steroid is an organic compound, with hundreds of steroid compounds found throughout nature. Steroids make up the structure of cells. Cholesterol, for example, is a steroid that composes the structure of cell walls.
Steroids can also act as hormones that act as signal messengers in the body. Most folks are familiar with steroid hormones like estrogens and testosterone.
Anabolic steroids are ones that act in the body to increase muscle and bone growth. These are the ones we often associate with professional body-builders.
A third class of steroids are corticosteroids. Corticosteroids are involved in a variety of functions within the body, including stress response, immune response, regulation of inflammation, and others.
There are natural corticosteroids produced by the body, like cortisol, and then there are synthetic man-made ones, like prednisolone.
What Does Prednisolone Do For Cats?
At lower doses, prednisolone may be used as an anti-inflammatory. A cat with a red, itchy skin infection for example, may benefit from an anti-inflammatory course of prednisolone to reduce inflammation and itching while antibiotics address the infection.
At higher doses, prednisolone can be used to treat conditions caused by an overactive immune system by suppressing its effects. This can include conditions like feline asthma, caused by the immune system’s response to airborne allergens, and inflammatory bowel disease, caused by the immune system’s response to food allergens.
PredisONE vs. PrednisOLONE
You might wonder why you’re reading about prednisolone, when prednisone is more common. You might also wonder if the two are basically the same thing. The simple answer is they are…and they aren’t.
Prednisone and prednisolone have the same effects on the body. This is because in most species, prednisone is very quickly converted to prednisolone by the liver. But a couple of animal species, including horses and cats, cannot efficiently absorb or convert prednisone to prednisolone.
So this is why, while we often use prednisONE with dogs, we should only use prednisOLONE in cats.
Side Effects Of Prednisolone In Cats
Cats tend to tolerate steroids better compared to dogs and we see fewer adverse effects in kitties. However, there are some important things to look out for, especially for kitties on higher doses of prednisolone.
Occasionally, a pet parent may observe their cat on prednisolone to have an increased water intake and subsequent need to urinate more. You might find yourself refilling the water bowl more often, and cleaning up larger urine clumps in the litter box.
Steroids can also cause an increase in appetite, which can lead to weight gain. For some conditions that cause weight loss, like inflammatory bowel disease, weight gain is desirable, but this is not always the case, so weight should be closely monitored.
Steroids may cause digestive upset in some cats, usually some soft stool or diarrhea if it happens.
Separate, long-term effects of prednisolone therapy can also be seen.
Steroids can contribute to increases in blood sugar in most animals, but in cats, this effect seems to be more prominent. For this reason, steroids should be used cautiously in overweight cats at risk for diabetes mellitus, and should not be used in diabetic cats, as steroid use will interfere with blood sugar regulation.
Long-term use of high doses of steroids can also lead to more serious side effects like a thinning haircoat, and ironically secondary skin problems. This, in combination with other effects like excessive drinking, urination, and appetite can be lumped into a condition known as iatrogenic hyperadrenocorticism, or synthetic steroid-induced Cushing’s disease. Fortunately, the effects are reversible if steroids are stopped.
And lastly, although the specifics are still debated, there is a perceived risk for cats at risk of heart disease developing heart failure on steroids.
This seems to occur uncommonly in cats with no signs or symptoms of heart disease. Steroids should be used with extreme caution in any cat with known existing heart disease.
As with any medication, using prednisolone must have benefits that outweigh potential risks, especially when used long-term.
Prednisolone For Cats: Dosage
Steroids like prednisolone have a very wide dosage range depending on the condition being treated. Lower doses are used to address inflammation while higher doses will suppress the immune system. Compared to dogs on prednisone, cats generally require higher doses of prednisolone.
Because of the high degree of variability in dosing, your veterinarian should decide what dosage of prednisolone will be best for your kitty.
Steroids like prednisolone are extremely useful medications because they have a broad range of dosage and effects. They are necessary to get some inflammatory and immune-mediated conditions we see in cats under control.
Cats are more resistant to steroid side effects than dogs. Steroids are also attractive options as anti-inflammatories especially given that our ability to use non-steroidal anti-inflammatories in cats is very limited.
All the same, steroids must be used judiciously and cautiously under the direction of a veterinarian. Also, remember that only prednisOLONE and not prednisONE should be administered to cats. So if you have a dog at home, don’t share any steroids prescribed for your pup (or for yourself) with your kitty.
Frequently Asked Questions
How Long Does Prednisolone Take to Work in Cats?
Generally, cats with inflammatory conditions will see improvement within just a day or two of prednisolone therapy. With more complicated conditions or immune-mediated conditions, noticeable improvement may take longer, but still generally within several days.
What Does Prednisolone Do for Cats?
Prednisolone is commonly used in cats as either an anti-inflammatory or as an immunosuppressive medication.
Inflammatory conditions may include any number of skin conditions, inflammation from an injury, or inflammation caused by arthritis.
Immune-mediated conditions where the immune system actually causes damage to the body in response to an initiating cause like allergens, may include feline asthma, inflammatory bowel disease, autoimmune diseases like immune-mediated hemolytic anemia, autoimmune skin diseases, and many others.
Prednisolone may also be used to treat and manage certain types of cancers, especially lymphoma.
What Are the Side Effects of Prednisolone for Cats?
The most common short-term effects in cats may include increased drinking, urinating, and appetite. Some cats may also develop mild signs of digestive upset, like diarrhea.
Over a longer time period, and especially at higher doses, we can see these short-term effects in combination with long-term effects like weight gain, thinning hair coat, and lethargy.
Steroids should be used very cautiously in overweight cats, as they can contribute to further weight gain. They may also increase blood sugar in cats more compared to other animal species, which may put an overweight cat already at risk for diabetes at an even higher risk.
Prednisolone should also be used cautiously in cats at risk for heart disease. Since many cats at risk for heart disease show no outwardly abnormal signs, your veterinarian may recommend a screening test, especially if long-term use of prednisolone is being considered.
Alternative treatment options to prednisolone therapy should be considered for cats diagnosed with diabetes or known to have existing heart disease.
How Much Prednisolone Can You Give a Cat?
Prednisolone, like all steroids, has a very wide dosage range, depending on its intended use. This is why your veterinarian should determine what dosage and protocol is best for your cat, depending on the condition being treated.