Zyrtec for dogs

While it may have never crossed most people’s minds, your dog can get allergies just the same as you do. So how do you help your furry friend get through the season?

Recently, a lot of vets have been prescribing Zyrtec for dogs as a method of treating allergies, despite the fact that it isn’t FDA approved for animals.


Zyrtec for Dogs

Why Vets Are Prescribing Zyrtec For Dogs

In case you aren’t familiar with Zyrtec, it’s an allergy medication that can be purchased at your local drug store. It’s used to treat symptoms like watery or itchy eyes, runny noses, sneezing, hives, and itching. Its main competitor is Benadryl, another well-known allergy medication. Unlike Benadryl, drowsiness with Zyrtec is often very rare.

The active ingredient in Zyrtec is cetirizine. Cetirizine is an antihistamine commonly used to treat itchy skin in dogs. It’s a popular prescription for canines because most dogs tolerate the medication very well, and it doesn’t have the effect of leaving your pet sedated and lethargic.

With the other allergy-fighting ingredients in Zyrtec and the fact that it can be purchased over the counter, vets often prescribe it as an affordable and effective method for combating your pet’s allergies.

While Zyrtec is generally safe for dogs, there are some precautions that you should keep in mind before administering it to your animal.


Precautions Before Giving Your Pet Zyrtec

Never give your dog Zyrtec-D. The “D” stands for pseudoephedrine, which is used to deal with congestion in humans. However, it can have lethal consequences if given to a dog. It overstimulates their central nervous system and heart, causing canine seizures, heart failure, and potentially death.

If your dog struggles with kidney or liver problems, giving them Zyrtec could make the problem worse. This is because Zyrtec can cause urine retention in animals. This isn’t too serious of an issue if your dog is healthy beforehand, but it could exacerbate preexisting issues in your pet.

Also, if your dog is nursing, giving her Zyrtec could be very dangerous for the nursing puppies. The ingredients in the allergy prescription can be transferred to the puppies through your dog’s milk.

Their bodies are too weak for a strong medication like Zyrtec, and it could lead to serious issues. The same goes for pregnant dogs.

It’s also possible that your dog may be allergic to antihistamines. If you give your dog Zyrtec and see a worsening of symptoms or lack of improvement, then they could be having an allergic reaction to the medication.

If this is the case, you should stop administering Zyrtec or any other medications containing antihistamines.

Make sure that you make your vet aware of any other medications that your dog is on before giving them Zyrtec. This is important when giving your pet any kind of medication, as some drug combinations can lead to negative effects.


Correct Dosage Of Zyrtec For Dogs

The safest way to determine the correct amount of Zyrtec to give to your dog is to consult with your vet. Generally, one tablet a day is safe for dogs to take, but the amount can vary greatly depending on your dog’s size and symptoms.

What kind of symptoms you are trying to combat in your will determine how much you should be giving them.

The tablets will almost always be administered by mouth to your pet. If given the proper amount, the side effects of the medication should be pretty minimal.

However, giving your dog too high of a dosage can lead to a worsening of symptoms and harmful side effects.


Signs Your Dog Is Suffering From Allergies

Signs Your Dog Is Suffering From Allergies

Allergy symptoms can be a little different in dogs than in humans. While we typically will experience itchy or red eyes and a runny nose, your dog’s allergies will most likely manifest in different ways.


The common symptoms include:



If left untreated, these can lead to more severe issues in your dog’s overall health, like hair loss and skin infections. A severe allergic reaction could even cause your dog to break out with hives or go into anaphylactic shock, which could be life-threatening.

Your dog could also develop something known as “atopy,” which is a hypersensitivity to certain allergens. While not as serious as anaphylactic shock, it can still create serious health problems for your pet. Fortunately, Zyrtec is very effective at combating signs of atopy.


Side Effects Of Zyrtec In Dogs

Side Effects Of Zyrtec In Dogs

So long as dogs are given a proper dosage of Zyrtec, side effects are usually nonexistent. Zyrtec is one of the safer medications you can give to your dog, so as long as you do so correctly and under your vet’s guidance, your pet should be good to go.

Zyrtec is also a difficult medication for a dog to overdose on. They have an extremely high tolerance for it, so long as they aren’t allergic to it.

There have even been tests performed on dogs where they were given more than 200x the normal prescribed amount for a human with no lasting health impacts.

That said, side effects can still occur, and it is always best to be on your guard. If you notice any of these side effects, stop administering the medication until you consult with your vet on how to address the issue.

The most common side effect of using Zyrtec for dogs is drowsiness. It’s still relatively rare, but it can occur when your dog is just starting to take the medication, or if the dosage is too high.

Smaller dog breeds are more susceptible to this side effect. Usually, this becomes less severe as your dog adjusts to the medication.

Other side effects include urine retention, vomiting, constipation, high excitement levels, or excessive salivation. Any time you are giving your dog a new medication, keep a close eye on them.

They aren’t able to communicate these problems to you as easily as a person could, and rely on you to monitor their wellness.

Alternatives To Giving Your Dog Zyrtec


Alternatives To Giving Your Dog Zyrtec

In the event that your dog does have an adverse reaction to taking Zyrtec, or you prefer a more natural form of allergy treatment, there are viable alternatives to the medication.

One of the natural alternatives to giving your dog Zyrtec is CBD. Studies over the past several decades have shown that cannabidiol can have a significant and positive impact on your pet’s well-being. You can find CBD products in the form of dog treats, oils, and even chewsThere’s no need to hide it in your dog’s food or worry about negative side effects.


Cannabidiol is useful for managing symptoms of dry and itchy skin, cracked paw pads, dull coats, and allergies. It also promotes the health of your dog’s skin, helping to reduce shedding and dandruff.

Another natural remedy that is helpful for alleviating allergy symptoms are natural supplements. These are great as well because they are well suited to animals of all ages.

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While the idea of giving your dog Zyrtec for their allergies might seem strange, it’s a proven and effective method for helping your pet cope with their symptoms. The side effects are minimal, and the positive effects go to work quickly.

Be sure that you consult with your vet beforehand to discuss whether or not Zyrtec could help your pet, and always dose based on their recommendations. And never give your dog Zyrtec-D.

Keep a close eye on your dog’s allergies before and after giving them the medication. If their symptoms worsen or show little signs of improving, then it might be time to consider a safer alternative.

Approved by:

Dr. Ivana Vukasinovic

Doctor of Veterinary Medicine, University of Belgrade

Ivana Vukasinovic grew up in Serbia and attended the University of Belgrade where she received a degree in Veterinary medicine in 2012 and later completed surgical residency working mostly with livestock. Her first year of practice was split between busy small animal practice and emergency clinic, and after two more years of treating many different species of animals, she opened her own veterinary pharmacy where an interest in canine and feline nutrition emerged with an accent on fighting animal obesity. In her free time, she acts as a foster parent for stray animals before their adoption, likes to read SF books and making salted caramel cookies.