The side effects of prednisone in dogs are not something you can afford to ignore when deciding if this drug is the right choice for your pup.
This article offers a case study of how prednisone affected an 18-month-old Boxer.
My pup had been healthy prior to the meningitis for which he was given the high-dose prednisone.
The meningitis was rough — but the prednisone treatment was equally awful. It has left us with a whole host of problems we’re still trying to fix to this day.
I am not a vet. This post is for general informational and educational purposes only. I encourage readers to see my full disclaimer here.
What is prednisone for dogs?
Prednisone is a steroid medication which can stop inflammation and, at its highest doses, suppresses the immune system.
It’s a very powerful drug. In one respect, it saved my dog’s life.
But prednisone causes many side effects, and they can be severe.
Prednisone is a double-edged sword. There is no getting around the fact that this drug does a lot of damage to the body.
Is prednisone safe for dogs?
Is prednisone bad for dogs? In many ways, yes. But, like I said, sometimes it’s a life-saving choice in an emergency, when vets don’t know what else to do.
Each dog responds differently to prednisone. There’s no telling how hard the drug will hit your dog. The side effects of prednisone in dogs will be much worse at higher doses. But even at low doses, prednisone side effects in dogs can be serious (see the skin condition calcinosis cutis below). The risk of serious side effects (even from low doses) goes up the longer your dog is on the drug.
This means two things:
- Keep the dose as low as possible.
- Keep the duration of treatment as short as possible.
Vets very commonly prescribe prednisone, usually mentioning only stomach upset and excessive hunger, thirst and urination as likely side effects.
It may be the only treatment for your dog’s condition. But check if there are alternatives that are gentler on the body.
My dog’s experience with prednisone
My dog took prednisone (prednisolone) for 11 months. He spent many of those months at very high dose. It was a godawful year. More than 10 months after completing treatment, we are still dealing with the consequences of this drug. I don’t know yet whether Shiva will ever be the same.
Prednisone or prednisolone for dogs?
The body breaks prednisone down into prednisolone. Give prednisolone and you save the liver that step.
What is prednisolone used for in dogs? All the same things as prednisone.
Prednisolone side effects in dogs are, unfortunately, the same as for prednisone. The two drugs will be referred to interchangeably in this article.
Which prednisone dose for dogs?
You can see from the pale blue chart below that the prednisone dosage for dogs varies widely, depending on what you’re trying to treat. This is because the drug has different effects at different doses.
Prednisone doses for dogs are described as milligrams per kilogram of dog weight per day. It’s well worth doing the calculations for the dosage your vet has prescribed so that you understand very clearly whether your dog is on a low or high dose and what kind of effect that is likely to have.
Prednisolone dosage for dogs is the same as for prednisone. Methylprednisolone doses are different. Methylprednisolone may achieve equal anti-inflammatory effect at lower doses.
What does prednisone do for dogs?
What is prednisone used for in dogs? Prednisone is very widely used by vets. They prescribe it for everything from itching to meningitis. It’s an ingredient in some ear drops for dogs.
At its lowest doses, prednisone basically supplements the dog’s own natural cortisol (in a dog with Addison’s disease, for instance). Slightly higher doses have an anti-itch (anti-pruritic) effect. At higher doses again it becomes anti-inflammatory. The highest doses switch off the immune system, as a way of treating “autoimmune” type conditions.
This is the riskiest level and comes with the most side effects.
12 serious prednisone side effects in dogs
Prednisone messes with virtually every aspect of the body’s functioning.
There is almost no end to the disturbing changes you may well notice in your dog.
I observed at least 12 distinct effects in my one pup.
1. Liver damage is one of the side effects of prednisone in dogs
Prednisone is very rough on the liver. It can cause severely enlarged liver in a dog and drastically elevated liver enzymes in a dog.
At one point Shiva’s liver swelled to the point that you could feel it as a lump in his side. The specialist did an ultrasound because he thought the enlargement might be a tumor. In blood tests Shiva’s liver values shot up astronomically high. Ultrasound for a dog can mean sedation and even anesthesia, so it pays to be aware that prednisone can cause this degree of liver enlargement, so that you might be able to reach a circumstantial diagnosis and forego the stress of the procedure.
The good news is the liver is an organ that regenerates. So if you can limp your dog’s liver through the time on prednisone, it can recover.
What is Denamarin for dogs?
Anecdotal reports from owners indicate that milk thistle for dogs can help support the liver while on prednisone, as can the milk thistle-containing supplement Denamarin. Denamarin for dogs side effects? As far as I could work out, this was a fairly gentle supplement with no worrying side effects I could find. My dog was on it for quite a few months. Of course, anything you put into your dog’s already overloaded system is something else for his body to process.
2. Prednisolone side effects in dogs: gut damage
Prednisone does a real number on the gut. Gastrointestinal problems may be the most common side effects of prednisone in dogs.
It may well be the biggest problem your dog is left to battle — potentially long after he’s finished his course of prednisone.
Can prednisone cause diarrhea in dogs?
Yes. Because of this, vets often routinely add a “stomach protectant” like omeprazole for dogs when prescribing high dose, long term prednisone. Of course, that’s yet another drug with its own suite of possible side effects. Some owners actually observe a worsening of their dog’s bloody diarrhea on omeprazole, so pay close attention to how it works or doesn’t work for yours.
At the very least, always give prednisone with quite a bit of food to offer some protection to the gut. Never give prednisone on an empty stomach, that’s for sure.
Regardless, you will need to rebuild your dog’s gut health once the prednisone is discontinued. We are now dealing with acid reflux that started just as my dog finished the prednisolone.
3. Ravenous hunger, thirst & excessive urination
Prednisone makes dogs wildly hungry and thirsty. With that comes excessive urination — and weight gain if feeding is increased. Many owners find their perfectly house trained pet begins having accidents. Some dogs experience leakage in their sleep. My dog was appalled when this happened to him. Be gentle and patient and use pee pads if they help.
If increased appetite, excess weight and peeing are your dog’s only side effects from prednisone, you are getting off very lightly.
4. Heavy panting at rest
Prednisone causes panting.
Your dog will be lying there almost asleep and puffing like a steam train. It’s quite distressing and something that often panics owners when it first happens.
I remember long nights counting Shiva’s breaths and googling “normal breathing rate dogs”.
Sometimes it can help to use cooling mats or a fan if your dog seems overheated. My pup stopped sleeping in his bed for several months while on prednisolone. He preferred to lie instead on the cool tiles of the bathroom floor. Beware the risk of hygromas developing from too much lying on hard surfaces.
5. Psychiatric disturbances
Many owners — myself included — have noticed profound personality changes in their dog on prednisone. It’s one of the side effects of prednisone in dogs that you never hear about.
The drug is known to cause psychiatric disturbances in human patients.
That certainly seemed like what I was witnessing in my dog. My outgoing, confident pup became skittish and easily frightened. He would bark at shadows and seemed to be seeing things that weren’t there. He displayed some aggression towards other dogs for the first time in his life.
6. Depression / withdrawal
There’s a fair chance prednisone will make your dog depressed.
It’s a recognized side effect. Dogs become withdrawn and antisocial. Mine would leave the living room where the family was gathered, go downstairs and put himself to bed in the toilet cubicle. He clearly felt terrible and wanted to be alone.
Owners often report that their dogs stop showing affection and stop interacting. As the prednisone dosage is reduced, your dog will come back to you. Comfort him, give him space. Let him be where he feels most comfortable. Maintain a quiet environment so he can rest.
7. “Cushingoid” state
The adrenal glands produce the steroid hormone called cortisol. When the adrenal glands produce too much cortisol, this causes Cushing’s disease in dogs (hyperadrenocorticism), sometimes mistakenly called Cushing disease in dogs or just called Cushings in dogs. (By the way, there is a treatment for Cushing’s dogs.)
Administering prednisone induces this same excess of steroids. Which is why your dog on prednisone can develop an array of problems that match the symptoms of Cushing’s disease in dogs. Your dog doesn’t have Cushing’s, as such, but is said to be “Cushinghoid”.
Pot belly and fat rolls
A Cushingoid dog typically has a pendulous abdomen.
This unusual pot belly in dogs is due to the redistribution of fat that prednisone causes within the abdominal organs.
Your dog might also have:
- hair loss or thinning
- fat rolls on the back of the neck
- bulging eyes
The drawing of the dog (above) from this article captures how my dog looked on prednisone.
He was 18 months old when he started the drug and aged 10 years in the space of a few months. He went from a bouncy puppy to looking and moving like an old, obese man. It was heartbreaking.
Have faith your dog’s appearance will normalize when the drugs are withdrawn.
NOTE If your dog has been so affected by prednisone as to become Cushingoid in appearance, he is likely to be more susceptible to adrenal insufficiency as the drug is removed (more on that later).
8. Adrenal glands
You’ll remember that, ordinarily, a dog’s adrenal glands produce the steroid hormone cortisol. And prednisone is a man-made version of cortisol.
How much cortisol the adrenals make is determined by a feedback mechanism.
So, when prednisone is present in the body, the body detects it as cortisol. In response, the feedback loop signals the adrenal glands to produce less of the hormone (since there’s already enough in circulation).
When prednisone is given in high enough doses for long enough, the adrenal glands stop making their own cortisol altogether. If this situation is sustained, the adrenals can shrivel up and atrophy. This is why it takes time for them to regain function when prednisone is withdrawn. You must taper slowly off the drug to let the adrenals gradually resume their cortisol-producing role.
Is once daily or twice daily dosing better for the adrenals?
What can you do to minimize the side effects of prednisone in dogs? Not much, other than use as low a dose for as short a time as possible. However, there is evidence that a once-daily dose of prednisone in the morning is less suppressive of the adrenals than twice-daily dosing. Read a study about that here. This means that at the point in the taper where you switch to once daily dosing from twice, the adrenals are likely to be waking up a little. It’s one of the reasons why a gradual taper is important.
9. Muscle weakness and muscle wastage
Prednisone interferes on a cellular level with the processes that build and maintain muscle. You will see muscle wastage. My very athletic male boxer faded away before my eyes. Spindly legs, no shoulder muscle to speak of. He was like a two-dimensional impression of a dog. At our lowest ebb he was so weak he couldn’t step up a single stair.
Owners often want to introduce a supplement to build muscle. It won’t do any good because what’s causing the muscle wastage is the prednisone, not any lack of nutrition. Giving a supplement will only burden the body with another substance to process. Hold fire and build back muscle slowly after your dog is off the drug. Some owners though say the muscle never returns to how it was before.
10. Calcinosis cutis and calcinosis circumscripta (skin lesions and lumps)
If your dog has skin lesions while on prednisone, check out our detailed article with photographs documenting this truly awful condition.
Calcinosis cutis and calcinosis circumscripta are often not immediately recognized by vets, so it may have to be you as the owner who diagnoses it.
The first sign of it in Shiva was on his tongue. You can see in the picture the white calcium deposits on the side of his tongue and underneath.
Unfortunately there is nothing you can do to resolve calcinosis. Nothing besides keeping the areas clean until you can get your dog off the prednisone. Then it will stop spreading and potentially resorb or push out through the surface and heal over. Antibiotics and other Hail Mary efforts will have no impact on calcinosis.
A biopsy can confirm diagnosis but this is probably an unnecessary stress (and an unnecessary anesthetic) for an already ill dog. If I had known what I know now, I would have been confident in diagnosing my dog’s skin lesions as calcinosis without the invasive procedure, which knocked him around.
11. Periodontal disease
Prednisone can wreak havoc with your dog’s dental health.
We’ve found success using raw meaty bones to bring Shiva’s teeth back to gleaming white after getting off prednisone.
While healthy dogs can easily neutralize the bacteria found in raw meat, I was never sure whether it was safe to raw feed a dog with a drug-suppressed immune system. We switched without problems to a raw, natural diet a few weeks after finishing prednisone.
12. Prednisone for dogs side effects: Infections
At its highest doses, prednisone achieves its therapeutic effect by suppressing the immune system.
Prednisone’s immunosuppressive effect means the body becomes much more susceptible to infection by pathogens that would normally cause no issue.
This can lead you down the path to multiple courses of different antibiotics to treat infection after infection. Although antibiotics may seem to clear the problem at least temporarily, they simultaneously inflict their own damage, particularly to the gut.
It’s a slippery slope and another reason to minimize the amount of time spent on prednisone and to use the lowest possible dose that gets the desired effect.
Vets and prednisone
Unfortunately, vets frequently prescribe prednisone without having much regard to managing the associated side effects. A specialist might prescribe the drug but then expect the local vet to deal with any complications.
“Get off the prednisone,” comes the advice. But your dog is on the prednisone in the first place to treat a serious and possibly life-threatening disease.
With the vets at a loss, you as the owner may very well be left with the task of deciphering the side effects and navigating all the various risks on your own.
It can be very scary. We felt completely at sea.
Getting off prednisone
You will dream of (and possibly fear) this day.
All the veterinary advice is that the prednisone taper for dogs must be done (painfully) slowly. This applies if the dog has been on the drug for any length of time longer than about a week.
The risk of stopping prednisone suddenly is that it can send the body into an “Addisonian” crisis. In other words, the body’s adrenal glands, after being suppressed for so long by the prednisone, haven’t had enough time to switch back on properly and so can’t make enough cortisol when the body encounters a stressor.
A full-blown Addisonian crisis is an emergency that can lead to collapse and even death. Addison’s disease is the opposite of Cushing’s disease. Where Cushing’s is too much cortisol/steroid, Addison’s is too little. As well as the body’s fight or flight response, cortisol is needed to regulate all sorts of functions in the body. The treatment for Addison’s disease is — you guessed it — prednisone.
The adrenal glands can take more than a year to fully recover normal functioning.
A quiet and predictable life is advisable during this time, with any changes introduced incrementally. Avoid over-excitement or too much physical exertion or stress. Stress can be caused by something as simple as a variation in routine or the addition of a new puppy to the household.
Steroid withdrawal / adrenal insufficiency
As the dose of prednisone is lowered, your dog might show signs of steroid withdrawal or adrenal insufficiency.
This is particularly likely if you step down the dosage quite a lot in one go. In some cases the signs of adrenal insufficiency mimic the symptoms of the disease for which the prednisone was originally given. Do your very best to avoid mistaking symptoms of adrenal insufficiency/steroid withdrawal for signs of relapse. Be aware vets can make this error too. If you bump the prednisone back up, thinking your dog is relapsing (when he is really just exhibiting signs of steroid withdrawal) this can set back treatment and unnecessarily prolong your dog’s exposure to the drug.
Whenever you lower the dose of prednisone, give your dog time to adjust. Some dogs can go a bit wobbly for a few days. But after a week or so their bodies should adapt to the new dose and you’ll see things stabilize.
The “physiologic” dose of prednisone
The potential for adrenal insufficiency heightens at the point in the prednisone taper where the dose dips below the “physiologic” level. (That’s the lowest possible dose of prednisone in that chart shown earlier.)
Lost? Let me explain.
Remember how I said prednisone is just a synthetic version of the cortisol produced naturally by the body? Well, the physiologic level of prednisone refers to the dose of the drug that matches the amount of cortisol the dog’s own adrenal glands would ordinarily produce. The natural level of steroid, if you like.
Below the physiologic dose, the artificial steroid provided in the form of the drug becomes low enough that the body’s feedback loop will detect a need for cortisol. In response to this trigger, the adrenals should reactivate, once again producing some steroid themselves — for the first time in a long time. This adjustment can be slow and it’s responsible for the wobbliness some dogs show at this point in the taper.
As we got to the lowest prednisone doses we experienced repeated instances of limps in both front and back legs. The limps came on suddenly. During this period my dog, on several occasions, injured himself during a walk. More than once he woke up limping.
In every case the limp would resolve after a day or two — or three — of rest.
There were so many prednisone-related weirdnesses that we got used to riding things out and not running to the vet every time something went wrong — which is what we had done at the start.
I now tend to think the limping was somehow tied to a detox process. When the drugs were withdrawn we also saw mucus in poops and paw cysts, which are known detox symptoms in dogs. All these things resolved on their own, without intervention.
Prednisone drug interactions with cyclosporine
If given together, these two immunosuppressant drugs can increase the effects of each other.
For a while my vet had my dog take both at the same time and his condition went rapidly downhill to the point that he could hardly get up. I insisted on discontinuing the cyclosporine and within half a day he was dramatically improved.
Beware anesthetic procedures after being on prednisone
If your dog has been on high-dose, long-term prednisone anytime within the past year and needs to have an anesthetic procedure, consider the need for a “steroid umbrella”.
This is where prednisone is given for a few days prior to, and after, the procedure. The idea is to support the body in case the adrenals’ ability to produce enough cortisol in response to the stress of the procedure is still impaired. It’s an approach used in human medicine too. You can read about it here. Vets mightn’t automatically think to do this with a dog. Make sure you do your own research. Make the vet aware your dog has been on prednisone recently. And make sure you know what is being done to account for that.
Explore whether the procedure can even be delayed to give your dog’s body more time to recover from the prednisone.
In conclusion: Day one of the rest of your pup’s life
Getting off prednisone is the first day of the rest of your and your dog’s life. Well done on making it through. There may well still be some hazardous terrain ahead, but at least now the drug can start clearing from his system.