How Much Zyrtec Can I Give My Dog?

Many dog owners are unaware of this, but dogs get allergies, too. The symptoms are similar to human allergies, which means that dog allergies also require proper attention and medication.

One of the widely prescribed treatments for dog allergies is the over-the-counter drug Zyrtec. Although it’s originally meant for human consumption, many veterinarians recommend this drug to treat allergy symptoms.

Before you give Zyrtec to your dog, you should first consult with a vet and learn about the product.

How much Zyrtec can I give my dog? When should you give your pet Zyrtec? What are its side effects? We will answer each of these questions in this article.

What is Zyrtec and can my dog use it?

Zyrtec is a popular antihistamine or medication for allergies. It contains the active ingredient cetirizine, which is known to relieve itchy and watery eyes, allergic rhinitis, hives, and itching in humans.

Although it’s not FDA-approved to use for animals, Zyrtec is safe and effective in dogs. That means your pooch will be able to handle the medicine well, and they won’t feel lethargic afterward.

Because of its safety and effectiveness, vets have been prescribing the product to treat or manage dog allergies. Additionally, it is affordable and available over-the-counter, making it ideal for many dog owners.

But, before you head to the nearest pharmacy to purchase this medicine, you should consider a number of things. This includes precautions, side effects, and correct use and dosage.

Proper Dosage and Use of Zyrtec

Zyrtec comes in tablet form, and it is simply administered through the mouth.

If you’re unsure whether you should give Zyrtec to your dog, you must consult with your veterinarian first. Your vet will tell you how much of the medicine you should give your dog and how often.

For dogs, Zyrtec (cetirizine) can be given between 0.25 mg and 0.5 mg per pound. Each dog is given a different dosage based on its age, weight, breed, and severity of the disease.

Generally based on your dog’s Weight,

  • Up to 10 pounds – 2. 5 mg (Once daily)
  • 10 Pounds to 20 pounds – 5 mg (Once daily)
  • 20 Pounds and above – 10 mg (Once daily)

However, different dogs may require a specific amount of the drug depending on the size and severity of the symptoms. Thus, when in doubt, ask a licensed veterinarian to assist you and help your canine friend feel better.

Precautions Before Administering

Zyrtec is generally safe for dogs. However, different dogs can have different reactions to this drug. Given this, it is ideal that you consult with your vet first.

Here are some precautions you should take before you give Zyrtec or Cetirizine to your furry friend.

  • Do not administer Zyrtec-D – This variant of the drug contains pseudoephedrine which is deadly for dogs. The active ingredient could cause seizures, high blood pressure, heart failure, and even death in dogs.
  • Make sure your pooch does not have renal or liver complications – One of the side effects of Cetirizine is urine retention. Thus, giving Cetirizine to a dog with liver or kidney problems may only make the situation worse.
  • You shouldn’t give Cetirizine to pregnant or nursing dogs or their babies – Puppies cannot tolerate potent drugs like Cetirizine. Hence, you shouldn’t use this medication to treat young pups, pregnant or lactating mothers. If you do, the ingredients in Cetirizine may be passed on to your dog’s babies through the milk.
  • Ensure that your pet has no allergy to antihistamines – Some dogs have allergies to antihistamines. As a result, administering Zyrtec will be futile, and your dog may end up in a worse condition.
  • If your dog has other medications, check if they are compatible with Cetirizine. may not be effective or safe in combination with other drugs.

What are the side effects of Zyrtec?

Zyrtec is safe for dogs as long as you give them the right dosage and use the drug for the right treatment.

In some cases, dogs do not overdose on Zyrtec, even if you gave your pet a little too much of it. That is to say, the drug is hardly unsafe for dogs since they have a high resistance to it. But, you have to ensure that your pooch is not allergic to antihistamines.

Nevertheless, side effects may still appear. As we’ve mentioned, dogs have different responses to the drug.

We have listed below some side effects you should look out for when you administer Zyrtec to your furry friend.

  • Drowsiness
  • Vomiting
  • Constipation
  • Urine retention
  • Sensibility/Irritability
  • Excessive salivation

If you notice at least one of the listed side effects in your dog, you should stop administering Zyrtec. Immediately bring your pet to the vet so that the doctor can provide you with professional advice and treatment.

When Should You Administer Zyrtec to Your Pup?

Of course, you should only provide your dog with this Zyrtec if your pup experiences allergy symptoms. Although the signs may not be the same as with human allergies, dog allergies also require proper attention and medication.

Below are some symptoms that tell you your furry friend needs antihistamine.

  • There is skin redness or irritation
  • Your pooch constantly rubs its face and snout
  • Inflammation
  • Your dog is chewing its legs and paws
  • Excessive itching

What are Alternative Treatments for Allergies?

In case Zyrtec is not suitable for your dog, there are other alternatives you can try to remedy dog allergies.

Alternatives like Claritin (loratadine), promethazine, and diphenhydramine are used by vets.

One of the best alternatives to Zyrtec is cannabidiol or CBD. This is a natural product used to treat dermatitis, cracked paw pads, and allergies.

It doesn’t induce any side effects, and it’s easy to take since CBD comes in various forms like treats, chewable, and oils. Additionally, cannabidiol also prevents skin diseases.


Although Zyrtec is originally made to treat human allergies, it’s also used to relieve allergy symptoms in dogs. Many certified vets prescribe this drug due to its safety and effectiveness.

Despite this, you should take precautions and monitor your pet for possible side effects. It’s best that you consult your trusted veterinarian before administering Zyrtec.