Veterinarian's Prednisone Side Effects for Dogs

If you've ever watched your dog struggle with an itchy rash that won't heal, chronic allergies, arthritis, or asthma, you're probably glad prednisone exists. Prednisone is a synthetic steroid similar to the hormone cortisol. Vets prescribe it for our dogs to treat a wide range of health issues.

Sick Old Dog
Veterinarian's Prednisone Side Effects for Dogs
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Prednisone uses can be short- or long-term. It's often prescribed for short-term use to get your dog over a health hump and back to his happy, lovable self. However, it's also used long-term to treat severe conditions like Addison's disease.

What is prednisone?

Prednisone is a manufactured steroid for dogs. It's an extra-potent form of the hormone cortisol. Cortisol is one of the two hormones produced by our dogs' adrenal glands; the other is aldosterone. Together they help keep the heart and gastrointestinal system healthy.

Prednisone comes in tablets, capsules, chewable tablets, drops, and injections. Vets most commonly prescribe prednisone dosages for dogs in the form of pills. They're small and can be easily hidden in peanut butter, cheese, or whatever treat you use to get your dog to swallow medicine. They're also inexpensive, which is nice.

What cortisol does

The hormone cortisol is often associated with the phrase "fight or flight." It helps our dog deal with stresses like being boarded while we're away, recovering from an injury, or something as simple as a change in her routine. It does this by helping to regulate blood sugar, blood pressure, and heart function. It also supports our dog's immune system.

When our dog needs a hit of high energy, cortisol triggers glucose production to provide it. When she needs to make the most out of her fuel, cortisol aids in the breakdown of fats, proteins, and carbs.

Cortisol, in the form of hydrocortisone, is found in creams and ointments readily available at the drugstore. You may have used it on yourself it to calm down a poison ivy rash or stop an itchy mosquito bite from driving you crazy. It's also available at pet stores for our dogs. It's best to use the kind made for dogs on your dog to avoid any reaction to other ingredients that are in the human version.

Prednisone dosage for dogs

With all the wonderful things naturally occurring cortisol does, our dog might still need more when he's having a health issue. This is where prescription prednisone comes in. It helps to suppress some of his body's own immune responses that lead to inflammation.

Prednisone pills come in 1, 5, 10, and 20 milligrams. Prednisone dosage for dogs is usually prescribed at the rate of 2.5 milligrams for every 10 pounds your dog weighs. A short-term course of prednisone is one to four or five weeks. It is given in an initial "blast," then very gradually reduced.

Tapering off prednisone

The reason prednisone is gradually reduced is to avoid withdrawal symptoms, which can be severe, even deadly. Whether you get the medication directly from your vet or order it online, it will come with specific instructions on how to taper it off.

For example, your 20-pound French bulldog might be given 5 milligram tablets to take once a day for five days, then one-half a tablet for five days, then one-half a tablet every other day for five days. This is just an example. Always follow the instructions your vet gives you to the letter.

Because prednisone is like the cortisol normally produced by our dog's adrenal glands, when we give it to her, the adrenal glands figure they can slow down their production of cortisol. If prednisone is stopped suddenly, it would come as a shock to her adrenal glands. By reducing the prednisone medication gradually, the adrenal glands have time to ease back into making their usual amount of cortisol.

Short-term side effects

While your dog is on prednisone, he could experience side effects. Prednisone side effects in dogs can be short- or long-term depending on how long your dog is on the medication. Short-term side effects include lethargy, increased appetite, thirst, and frequent urination.

Vomiting and/or diarrhea can also happen. If either of these occur, a call to the vet is in order. Either or both of these symptoms can quickly lead to dehydration and cause a host of other problems.

One way of helping your dog cope with increased appetite is to break his meals up into smaller but more frequent feedings. You could also try giving him a bully stick to chew on between meals. It's OK to let him drink as much as he likes but you'll want to take him out frequently. If he has an accident in the house, understand that he can't help it.

Long-term side effects

Some health conditions require long-term use of prednisone. With long-term use comes a new set of prednisone side effects in dogs. They include obesity due to increased appetite (and our difficulty saying no), a dull and/or thin coat, and hard spots of calcified minerals in her skin.

Prednisone's anti-inflammatory effect can, unfortunately, also suppress your dog's immune system. So should your dog become injured while on long-term prednisone, it may take longer for the wound to heal. She'll also be more susceptible to common fungal and bacterial infections.

In addition to being more susceptible to infections, because of prednisone's anti-inflammatory effect, your dog may not show any signs that she's sick. So your vet might want to periodically check your dog's urine to make sure she doesn't have a bladder infection. You and your vet will have to weigh the advantages of having your dog on long-term prednisone against the risks and side effects.

When prednisone cannot be used

Although prednisone is considered to be a pretty safe medication for dogs, there are times when it should not be prescribed. A female dog that is pregnant or nursing puppies should not take prednisone. Neither should it be given to dogs that are being bred or puppies less than 6 months old.

If your dog has another serious illness like diabetes or cancer, prednisone is probably not a good idea. And, if your dog has a heart problem, prednisone may not be an option.

Cushing’s disease and prednisone

Cushing's disease is a condition in which your dog's adrenal glands produce too much cortisol and aldosterone. The disease usually develops naturally, but it can also be brought on by a dog taking too much prednisone, or too-frequent, long-term use of ear or eye drops, creams, or ointments containing hydrocortisone.

When a dog develops Cushing's naturally, it's most often due to a tumor in his pituitary gland. The tumor signals the adrenal glands to produce more and more cortisol. Cushing's is most likely to occur in older dogs, so the symptoms can easily be mistaken for natural signs of aging.

Breeds that seem to have a higher risk of developing natural-occurring Cushing's disease are beagles, Boston terriers, boxers, dachshunds, and poodles.

Cushing’s disease symptoms and treatment

Because your dog's adrenal glands are making too much cortisol, the natural version of prednisone, some of his symptoms will be the same as prednisone side effects. Dogs with Cushing's drink and urinate a lot, and they gain weight. Skin conditions and weakness can also occur as the disease progresses.

Treatment of naturally occurring Cushing's consists of prescription medicines that eradicate part of the adrenal cortex. So while the pituitary gland tumor still signals the adrenal glands to produce more cortisol, the adrenal glands aren't able to respond. When excessive use of prednisone or products containing hydrocortisone is the cause of your dog's Cushing's, she will usually get better when you stop using the medication.

Diagnosing Cushing's can be tricky, so several different lab tests will probably be needed. The average age a dog acquires natural-occurring Cushing's is 8 years old. Dogs with this type of Cushing's usually pass away within a couple of years after developing the disease. However, it's important to note that these Cushing's dogs are almost always older at onset.

Addison’s disease and prednisone

Addison's disease is the opposite of Cushing's. With Addison's your dog's adrenal glands produce less than normal amounts of cortisol and aldosterone. Addison's is usually caused by an autoimmune response in which your dog's own immune system goes haywire and the body attacks its own organs.

While the average age of a dog with naturally occurring Cushing's is 8 years old, Addison's is a young dog's disease, and it occurs more often in females. The average age a dog develops Addison's is 4 years. While dogs with Cushing's often pass away within a couple of years, with proper treatment, a dog with Addison's can live a long, relatively healthy life.

Addison's can be a hereditary condition. It can also be brought on by abruptly stopping your dog's prednisone instead of tapering it off. Other, less likely causes of Addison's are an adrenal gland infection or injury. Some of the breeds that may have a higher risk of developing Addison's are Great Danes, Portugese water dogs, and standard poodles.

Addison’s disease symptoms and treatment

Because the adrenal glands of dogs with Addison's aren't doing their job, an Addison's dog cannot handle stress well. He may have a decreased appetite, depression, diarrhea, vomiting, and overall weakness. Addison's disease symptoms may occur very suddenly or they may appear gradually and intermittently.

If you think your dog may have Addison's, document his symptoms and see your vet. Bloodwork on an Addison's dog will usually show high levels of potassium and low levels of sodium. Once your vet has determined that it's Addison's, and treatment begins, your dog will usually start to feel better pretty quickly.

Addison's is not curable but its symptoms can be well-controlled with prescription medications like prednisone. The prednisone provides what the adrenal glands are not able to produce. Your vet may also advise you to do what you can to minimize stress in your dog's life.

Natural alternatives

Prednisone is most often prescribed to reduce inflammations ranging from respiratory inflammation due to allergies or joint inflammation from arthritis. If you want to try reducing inflammation naturally, you might consider dietary changes and products that ease inflammation.

Reducing your dog's intake of grains by feeding her a dog food that is grain-free is a good start. These foods can be more expensive but you usually feed less of them than the cheaper grain-packed varieties. You might also consider switching her to a raw diet. Adding probiotics that can ease gastrointestinal issues may also help.

Some nutritional supplements that can help with inflammation are turmeric, omega-3 fish oils, antioxidants like vitamins E and C, and beta-carotene. Glucosamine and chondroitin, as well as hyaluronic acid, may help with joint inflammation and pain. Yucca and cannabidiol, also known as CBD oil, have also been used successfully to treat inflammation.

Minimizing side effects

Prednisone side effects in dogs are dealt with differently depending on whether your dog is on short- or long-term prednisone therapy. If he's experiencing side effects on a short course of prednisone, with input from your vet, you may just have to weather through it.

However, if he's on prednisone long-term, your vet may have to consider reducing the dose or trying another type of corticosteroid. If reducing the dose, your vet will need to figure out the lowest dose your dog can be on to treat the problem but minimize the side effects.