Atarax For Dogs – A Pet Owners’ Guide To What It Does And How It Works

Atarax For Dogs

Welcome to our complete guide to Atarax for dogs. When vet’s prescribe our pets medication, it can be hard to remember all of the questions we should ask at the time. After all, having a poorly pet can be overwhelming. These questions often come to you as you are walking down the road later on, or pottering about in the kitchen. So don’t worry, and keep reading.

Allergies in dogs

Our dogs get sick sometimes. It’s a fact of life. When this happens we want to provide them with the best care we possibly can. With conditions as uncomfortable as severe allergies, it can be distressing just to see our dogs suffering form them. Allergies occur when our dogs’ immune systems overreact to allergens. These are found in substances everywhere, and can include dust, pollen, chemicals, and even the food your dog eats.

When your pup’s immune system comes into contact with the allergen, it makes a protein called IgE. This protein causes your dog’s body to release histamines. And these are the chemicals that cause the allergy symptoms. Hence the common anti-allergy medicine name ‘antihistamine’. And Atarax for dogs is just one example of a canine antihistamine.

Atarax for dogs

Allergic reactions can range from almost undetectable, to serious and life threatening. So, we have to have treatments ready for when our dogs are uncomfortable.

Atarax For Dogs

Atarax is a brand name for hydroxyzine. This drug is one of the large family of anti-histamines that vets have at their disposal. It is a prescription-only drug, and as such you won’t be able to get hold of it without going through a vet.

An antihistamine, as the name might suggest, works against the histamines in your dogs system. Histamine is produced in abundance during an allergic reaction, and this overflow can cause pruritus (itchy and inflamed skin) and even respiratory issues. Antihistamines block your body’s histamine by attaching to the receptors that were meant for it, lessening the effect they can have.

This isn’t just something we do for our dogs. If you take medicine for hay fever at certain times of year, it’s likely an antihistamine. By inhibiting the histamines in our dogs symptoms we can lessen allergic reactions by striking directly at their cause.

Atarax and the FDA

Atarax, and other brands of hydroxyzine, is not licensed by the FDA for use in animals, but is still used regularly by vets. It seems odd, but this is quite common. The AMDUCA allows the use of medicines that are not licensed for animals at a vet’s discretion. This is the case because a lot of useful medicines for veterinary medicine have not yet been licensed as such in the US.

Let’s look at the reasons for using this medication. What specific allergic symptoms or causes would warrant an Atarax prescription?

What is Atarax used for in dogs?

Atarax for dogs is often leaned towards in cases where dermatitis and pruritus is a major factor. This is because Atarax has shown considerable benefit in these circumstances. When a dog has a severe skin reaction due to an allergy, it’s often referred to as atopic dermatitis. So if your pup is experiencing itching and skin irritation, and an allergy could be the cause, then he may well be prescribed with Atarax for dogs.

It’s even possible that Atarax, or the same drug by a different name, might be combined with another medicine or prescription dog food to help improve the results. The combination of increased fatty acids in the diet and an antihistamine has been shown to produce good results in clinical studies.


Combining Atarax with prescription food for example, is usually done to try and prevent the need to use steroids. This is known as steroid sparing. Steroids can have more serious side effects than antihistamines, so if vets can avoid using them they will. Sometimes, though, this is unavoidable and your vet may need to simultaneously prescribe an antihistamine and a steroid.

One example of such a treatment is Temaril P. This is because of the powerful effect steroids can have on the symptoms of an allergic reaction. It’s also likely that this might not be the only anti-histamine your vet will try.

Alternatives to Atarax

A 2013 trial weighing up a combination of hydroxyzine and chloralheniramine against another antihistamine actually found the other, dimentiden, to be more effective. This isn’t a reason to worry if he is prescribed Atarax for dogs. Just proof that there are other options out there if it doesn’t work, before resorting to steroids.

So, just how much atarax will my dog be receiving? We all know that dosages are important with every medicine.Too little won’t do anything yet too much could result in a dangerous overdose. Let’s talk about what constitutes the right amount of Atarax for dogs.

Atarax Dosage for dogs

Atarax dosage for dogs can vary a lot, depending on weight and the severity of their symptoms. The prescribed dose can be anywhere from 0.5 – 2mg per kg. This dose is taken either three times a day, or sometimes four. The exact dosage necessary to resolve symptoms will be decided on by your vet when they see your dog. This is one of the reasons the drug is prescription only. You could very easily give too little and have absolutely no effect on your dogs condition.

The vast range of doses means that Atarax 50mg for dogs would be right for dogs of two vastly different weights.

Can my dog overdose on Atarax?

As ever, there is the potential for an overdose. It is essential to stick to the dosage prescribed to your dog, as an overdose can be really severe. Overdosing on a 1st generation antihistamine like Atarax can be fatal. When this happens it’s because of a phenomenon called CNS hyperexcitability. This disorder of the nervous system can cause organ failure and subsequent death.

The exact dangerous quantity of Atarax for dogs is unclear. However, vetinerary professionals accept the manufacturer’s dosages as safe. Due to this danger, if you accidentally give your dog too much Atarax, or your dog gets into your medicine cabinet, it’s best to take them to a vet straight away.

As always with these things, usually dogs are fine, but when the risk is death, usually is not good enough. When the vet prescribes medicine for our our dogs it can be quite daunting. We’re usually almost as concerned with the potential negative effects as we are with the positive ones.

Atarax Side effects

No medication is without side effects. What we look for is a medicine where the side effects are preferable to the condition they’re treating. It’s worth pointing out that while all these effects are possible, most dogs will take this medication with relatively little in the way of side effects. Atarax for dogs has side effects in common with other first generation antihistamines. The main ones are vomiting and diarrhea. This won’t happen to every dog, but fortunately it is more likely than some of the more severe potential side effects. It’s also quite normal for most medications to have this affect.

As with a lot of other medicines, the best way to combat stomach upset with medication is to make sure your dog takes the medicine with food. Food lines your dogs stomach. As a result, the medicine absorbs more slowly and won’t irritate the gastrointestinal tract. Other side effects more related to antihistamines can include drowsiness, blurred vision, and urine retention.

When to talk to the vet

If any of these become enough of an issue to become noticeable, it might be worth talking to your vet. Your vet will be able to check your dog and make sure his response to this drug isn’t particularly exaggerated.

It’s important to note that interaction with other drugs, especially other antihistamines, could cause side effects to become more pronounced. To prevent this from happening, make sure your vet is aware of any medication you are giving your dog. It’s a good rule of thumb, no matter how innocuous a supplement or medicine may seem.

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Pregnant dogs should not take Atarax or any other of hydroxyzine. This is because hydroxyzine is teratogenic. This means it can alter the development of the fetus inside a pregnant dog. A dog whose mother was taking hydroxyzine while she was pregnant will likely have birth defects. Alternatives are available for pregnant dogs, and vets will always take this into consideration.

Atarax for dogs

To sum up, Atarax is an effective medicine that makes up part of our arsenal when fighting against the suffering created by allergies. This antihistamine is particularly effective for allergies involving skin reactions, a common problem among many dogs. This is a much lower risk treatment than some of the alternatives for allergies. The range of treatment options we have available mean that, if your vet has prescribed it, Atarax for dogs has a good chance of helping your pet with minimal complications.

Remember, your veterinarian is the best person to decide which drug is right for your dog. If you have any concerns, don’t hesitate to talk to them or get a second professional opinion from another qualified vet.


The Labrador Site Founder

Pippa Mattinson is the best selling author of The Happy Puppy Handbook, the Labrador Handbook, Choosing The Perfect Puppy, and Total Recall.

She is also the founder of the Gundog Trust and the Dogsnet Online Training Program 

Pippa's online training courses were launched in 2019 and you can find the latest course dates on the Dogsnet website


  1. HI I want to put my lab/fretiever on Atarax but my vet cannot find it can you tell me where in Auckland N Z where I can get it for the vet