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    Prednisone Side Effects in Dogs

    Prednisone is a corticosteroid, which is a class of drugs with anti-inflammatory properties, commonly prescribed for many ailments affecting dogs. If the name sounds familiar, it’s because it’s also a human medication.

    In some cases, if a dog has a severe disease, it can even save its life. We have researched the essential facts you need to know about prednisone and its side-effects so that you can make an informed decision about using it as a treatment for your dog.

    How Does Prednisone Work in Dogs?

    Prednisone, a synthetic steroid, can be used for a variety of diseases, particularly for anti-inflammatory or autoimmune diseases. It may also be used for allergies when other medications don’t work.

    Corticosteroids like prednisone are steroid hormones that affect a wide range of biological activities in people and animals — like maintenance of blood electrolyte levels, metabolism of nutrients, and control of inflammation. It can also regulate stress and immune system responses.

    How Long Does It Take Prednisone to Work on a Dog?

    A vet will usually administer prednisone after diagnosing an anti-inflammatory or autoimmune disease responsive to steroids.

    Usually, it is started and maintained at a low dose. When injected, this steroid can provide relief within one to four weeks.

    During your visit to your local vet, it is important to ask “how long does prednisone stay in a dog’s system?” In humans, the half-life of the drug is about three or four hours. This means in about three hours at least half of it will have been cleared.

    The rest will take five-and-a-half times or more of the half-life. So this can be anywhere from 16 to 22 hours.

    Calculating the half-life of prednisone in dogs and how long it will stay in their system will also depend on the weight and size of your dog.

    What Are the Effects of Prednisone in Dogs?

    As a synthetic corticosteroid, prednisone mimics the effects naturally occurring corticosteroids should produce.

    However, since it is many times more potent and lasts longer, it can treat issues that a normally robust immune system wouldn’t able to handle.

    For instance, it’s an effective treatment for eye and skin problems, for severe allergies or arthritis, and for blood and breathing disorders. Since the drug has anti-cancer effects, too, prednisone for dogs with cancer helps them feel better if they have lymphoma, which is the most common type of cancer for dogs.

    Prednisone dosage for dogs with lymphoma depends on many factors, including the stage of lymphoma. In stage I, this cancer involves a solitary lymph node, but by stage V it involves the bone marrow.

    What Are Some Common Prednisone Side Effects in Dogs?

    The common side effects of prednisone are not unique to the drug but are common with almost all steroids.

    Another thing to note is that if your dog is on prednisone and is either pregnant or nursing, close supervision of possible side effects is necessary.

    Prednisone’s Common Side Effects in Dogs

    Prednisone can result in side effects like increased thirst, hunger, and panting. Your dog may also feel lethargic or have gastrointestinal issues like vomiting and diarrhea.

    Additionally, your dog might get skin infections or existing infections may get worse.

    Symptoms can also prove inconvenient for households. One issue, for example, is frequent dog prednisone urination.

    Since corticosteroids create a mineralocorticoid effect this triggers an increase in water consumption. This may then lead to urinary incontinence.

    Restricting water for a dog on prednisone in an effort to reduce urination in the house places an unnecessary hardship on your dog. It may be necessary to allow your dog to spend more time outdoors.

    Prednisone’s Infrequent and Rare Side Effects in Dogs

    Infrequent and rare side effects of prednisone include intestinal or stomach bleeding, diabetes, osteoporosis, Cushing’s syndrome, more white blood cell production, low calcium in the blood, or thin and fragile skin.

    Are the Side Effects Immediate?

    Side effects can occur when steroids become effective. Steroids begin to work anywhere from the first week to as long as a month.

    More Serious Prednisone Side Effects in Dogs

    Bad reactions to prednisone usually occur with overdose or long-term use. If your dog has to stay on it for a long time, your vet may suggest you administer the drug every other day, or even less to reduce possible serious side effects.

    If your vet does give you such instructions, try to follow their recommended dosage schedule as closely as possible as this will prevent problems resulting from overdose.

    What Are the Long-Term Effects of Steroids on Dogs?

    Some diseases require long-term treatment of 3 to 4 months at strong enough doses to reduce inflammation or suppress immune system reactions.

    During this time, your dog may show side effects like urinary tract infections (UTIs), a thin coat of hair, and slow wound healing. Your dog may also have an increased appetite and increase weight rapidly, even to the point of becoming obese.

    At the same time as your dog is gaining weight, its muscles may become increasingly weaker because of protein catabolism.

    If you notice hard plaques on the skin, it is a condition called “calcinosis cutis,” which is a result of calcium deposits in the skin. Your dog may also become increasingly susceptible to bacterial and fungal infections or develop adult-onset demodectic mange, a condition caused by skin mites.

    Another serious long-term effect of steroids is that your dog may be predisposed to get diabetes mellitus.

    Prednisone Dosage for Dogs

    Because strong dosages and long-term use may create serious adverse effects, most vets prefer to use prednisone in low doses for a short time.

    They only waive this rule of thumb if the dog has a severe or life-threatening disease. Under these circumstances, the effects of not taking prednisone are far worse than the side effects that might occur.

    In an effort to keep the dosage low, vets often recommend 0.5 mg/lb of prednisone as an anti-inflammatory or 1 mg/lb as an immunosuppressant. Besides estimating dog prednisone dosage by weight, the amount of dosage may also depend on the disease.

    Your vet will be able to advise you on the dosage amount for different diseases; for instance, the prednisone dosage for dogs with arthritis, prednisone for dogs’ allergies, and so on. As you’ve probably already surmised, dosage rates also depend on other factors: the age of the dog, the disease, and the dog’s weight.

    Prednisone can be administered as a chewable tablet, as an oral liquid, or as an injection. If the tablets or oral liquid is added to food, you will have to observe how much of the food is eaten to make sure that your dog is getting enough of the medication.

    When to Consult Your Vet

    Consult your vet if your dog has symptoms that suggest a weak immune system, an inflammatory condition, or arthritis.

    • Symptoms that suggest a weak immune system include skin, ear, or eye infections or problems with breathing (which might be indicative of bronchitis or pneumonia.) Other symptoms could be a loss of appetite, or gastrointestinal issues like nausea, vomiting, or diarrhea also suggest a weak immune system.
    • Symptoms that suggest an inflammatory condition include flu-like symptoms, like fever, chills, fatigue, loss of appetite, and stiff muscles.
    • Symptoms that suggest arthritis are low energy levels or difficulty in walking or running. Besides fatigue, arthritis affects the joints, creating joint tenderness, swelling, stiffness, and pain. If your dog is lethargic and appears to have a loss of joint motion, it could be due to arthritis.

    Even if these symptoms appear mild, they may be indicative of other, even more serious health issues. For instance, what appears to be flu might suggest a serious inflammatory disease like Addison disease, inflammatory orthopedic disease, asthma, neoplasia, or immune-mediated hemolytic anemia.

    Risks of Prednisone in Dogs

    The risks of prednisone are based on long-term, high-dose side effects like Addison’s disease, Cushing’s disease, diabetes, ulcers in the digestive tract, or a heart attack.

    Another risk is canine prednisone withdrawal, which occurs when you abruptly stop giving it the drug. You have to taper off the prednisone dosage or they will get severely ill.

    Risks are also due to drug interactions with other medications your dog might be taking for blood thinning, antifungal infections, or nausea. In fact, there are about 774 drugs that interact with prednisone.

    Prednisone Interactions

    When talking to your vet, inform him about any other medications that your dog may be on.

    Prednisone interacts with non-steroidal anti-inflammatory drugs, other steroid medications, diuretics, and insulin. It also interacts with digoxin, mitotane, phenobarbital, and ketoconazole.

    You also need to be aware of the fact that if your dog is getting vaccinations, these will be less effective.

    Can You Give a Dog Human Prednisone?

    Although it might seem both logical and frugal to share any prednisone you or a family member may be taking with your dog, this is not a good idea.

    For one thing, your human dosage may be stronger.

    For another, your dog needs to be under a veterinarian’s supervision for health conditions that require prednisone. Steroids are powerful and adverse reactions need to be monitored by a trained observer who understands the risk of overdose.

    What Other Drugs and Treatments Are There for Your Dog?

    If you do not wish to put your dog on prednisone because of the possibility of side effects, there are three other alternative health medications and treatments:

    1. You could give your dog CBD oil to reduce inflammation.
    2. You could give your dog natural remedies that either reduce inflammation or boost the immune system like turmeric, yucca root, licorice root, ginger, or comfrey.
    3. You could improve your dog’s diet and go for more walks to get more exercise.

    However, these alternatives are not always as effective as prednisone. They may take longer to act and may not act as powerfully as a steroid.

    Whether you choose them over prednisone depends on the severity of your dog’s disease. If your pet has a life-threatening illness, then prednisone may be the better option.

    It’s always a good idea to speak to your vet before you decide to use non-pharmaceutical remedies and treatments rather than prednisone.


    Prednisone could have your dog wagging its tail again because corticosteroids like this one can be the best solution if your pet needs a life-saving medication or has a debilitating health condition that compromises its quality of life.

    Although there are many conflicting opinions about giving dogs a steroid, you have to keep in mind that vets do so with an abundance of caution, only suggesting this course of action if they firmly believe that a more natural solution will be too slow or ineffective. In some cases, the benefits of taking a steroid outweigh the risks of side-effects.

    Also keep in mind that when the medication is used properly, few, if any side effects, may occur.

    When administering this drug, work closely with your vet to make sure that you are sticking to the right frequency and dosage. Your vet will also be in a position to tell you why your dog is acting weird on prednisone.

    For instance, many pet owners complain that their housebroken dogs begin to pee before they can get them outdoors. They complain about “prednisone making my dog pee.”

    When this or other unusual behavior happens, like unexpected aggression, it is important not to punish your dog as they are suffering from urinary incontinence.

    Besides helping you figure out how to deal with side effects, a vet can also help you figure out how to progressively reduce the dosage if you need to take your pet off the medications. If your vet decides that your dog does not respond well, then he or she will give you a schedule on how to wean your dog off the medications.

    Since simply stopping the administration of prednisone even if your pet does not react well to it could cause medical complications, you must remain patient, follow your vet’s instructions, and gradually taper down the dosage.