Can Drinking Too Much Be Harmful to a Dog on Steroids?

The most common steroid side effect is drinking a lot of water. But can this actually harm your pet and what else might be going on if your dog suddenly becomes really thirsty?

is drinking too much a problem for a dog on steroids

The vet prescribed 20 mg of prednisone once a day for a possible problem for my 80 lb. golden retriever. I know prednisone makes them thirsty, but he’s drinking 1.5 gallons of water per day. He’ll be on the prednisone until January 8th. Can that much water harm him in any way?

My first question today is from Earl, who writes that his vet prescribed his Golden Retriever with prednisone and he knows that prednisone can make them thirsty, but this dog is drinking an awful lot and he's going to be on this drug for quite a while.

Can that much water harm him in any way? This is really the question today.

Steroid Side Effects

I'm going to start off by saying the two biggest side effects when we’re giving steroids, especially when steroids are started or if they're given at high doses, are an increased appetite along with drinking and urinating a lot, which is what this dog's likely doing.

Peeing lots

The increase in thirst is really a result of the peeing. The dog is actually producing larger volumes of dilute urine because it is on steroids, and so it needs to maintain its hydration levels just by drinking more.

It’s important from this point of view, never to limit their water intake because it's not the drinking that's causing the problem, it's the urination.

If you are taking steroids or you're giving your dog steroids for any reason at all, it's really important that they should always have access to plenty of fresh drinking water. If you limit that water it’s not going to change the amount of urine that they're producing. It's not going to stop any accidents that they might be having or they might have. What it could do is it could lead to your dog becoming really dehydrated and it's important that this obviously doesn't happen.

Want to know more? Check out my complete guide to steroids for pets!

How Much Water is Too Much?

Now, if we think of what excessive drinking is in general, normal water intake is typically around 50 ml per kilo per day. Excessive drinking level, which is what we call polydipsia, being defined as drinking more than 100 ml per kilo per day. Over twice what this normal level would be.

For this 80 lb dog that would equate to just over one gallon or a little over 3 ½ liters to be considered abnormal.

Now, Earl says that his dog is drinking 1-½ gallons so that clearly says that it's abnormal, but we know why that's happening because this dog is on steroids.

an increased appetite, drinking more and urinating more are the most common steroid side effects in dogs

Other Causes of Excessive Drinking

For a dog that wasn't on steroids then this level of drinking should actually trigger testing to try and diagnose what the problem is because clearly, it's an excessive amount.

Drinking and urinating really are common symptoms for a whole load of different conditions, especially conditions of older age. These can include diabetes, liver disease, kidney disease, some hormone abnormalities and many other conditions as well, including some cancers.

And so we shouldn't ignore the fact that our dog is drinking more than they used to.

Some dogs don't need to drink these high  levels to be classed as abnormal. If your dog isn't a particularly big drinker, and especially if they are getting wet food where they will be getting a lot of water from their food, you shouldn't wait until they are drinking ridiculously large volumes before you start to think that there's something wrong.

Any increasing levels of thirst or peeing a lot more should trigger an investigation and so a trip to your vet.

Diagnosing the cause

Ideally, if you take a urine sample with you when you see your vet that would be great. The most useful urine sample is the first one that they produce after being asleep all night because it’s the one that should be concentrated and that will be concentrated if there's not really a problem. If it's still dilute, then that will trigger blood testing and other investigations.

Now, in this case, drinking that amount is not going to cause any problems. What it’s doing is maintaining hydration and problems will potentially come about by restricting this water intake.

Discuss Problems with your Vet

If you're having problems with your dog having accidents, so they're peeing overnight, they're having accidents in the house, it is tempting to say, “Well, the steroids are causing problems and I'm just going to stop them.” But it's important to say that steroids should never be stopped suddenly.

The dose should always be tapered down slowly. The reason for this is that stopping steroids suddenly can cause something known as an Addisonian crisis and that can actually be fatal.

What happens is your dog’s body stops producing stress hormone because you're giving extra steroids through the medication and it takes a little while for that to kick back in. And what happens if you stop suddenly, is that there's no stress hormone and that's really actually important for the body to function in a whole load of different ways and you get something called an Addisonian crisis.

Follow any medication instructions

It's always important to follow your vet’s instructions with whatever medication you're giving and certainly, with steroids, it's important that we wean them off slowly.

If you are getting severe side effects that either you or your dog are struggling to cope with, then really always talk to your vet before you change treatment to see if there are any other things that you can be doing to help manage those side effects a little bit more effectively and to make sure that we're not getting into dangerous situations by just stopping the medication.

The above is a transcript taken from “The Dr Alex Answers Show”.

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