Is Hydroxyzine for Dogs A Good Idea?

Hydroxyzine is an antihistamine that was approved by the FDA back in the 1950’s. You may not be sure what an antihistamine is but that is okay, and that is why I am here to inform you about what hydroxyzine is and the reasons as to why hydroxyzine for dogs is safe.

An antihistamine is a drug that fights off allergy symptoms. So, what does this have to do with dogs and how does it affect dogs? That is the exact thing this article will answer. By the time you are finished reading this article, you will have a good understanding about hydroxyzine.

1. What Does Hydroxyzine Do?

2. What Are the Ingredients of Hydroxyzine?

3. Why for Dogs?

4. How Does Hydroxyzine Help with Allergies?

5. How Does Hydroxyzine Help with Atopic Dermatitis?

6. How Does Hydroxyzine Help with Anxiety?

7. How Does Hydroxyzine Help with Itchiness?

8. How Does Hydroxyzine Help with Rashes on Skin?

9. What Are the Side Effects of Hydroxyzine in Canines?

10. What Research Has Been Done?

11. What Hydroxyzine Dosage is Safe for Your Dog?

12. What If Overdose Happen?

13. Conclusion

What Does Hydroxyzine Do?

Hydroxyzine has many different things it can do to the human body. Chemically saying, it is a first-generation antihistamine of the diphenylmethane and piperazine class. It was first formulated in 1956 and marketed by a big brand in the United States the same year.

Hydroxyzine acts as an antihistamine which reduces the natural histamine in our bodies. What does this mean exactly? Well, it means that hydroxyzine effects the receptor system in the human brain.

In humans, it can take away the sneezing, runny nose, or even hives on the skin that occur in many allergic reactions. But most importantly, it is used to treat anxiety and tension that occurs due to disorders like psychoneurosis. It is also used to treat hyper cases of hyperalgesia and motion sickness that causes nausea.

Although hydroxyzine is sedative and hypnotic, interestingly, it does not have any limitation or potential to be abusive or addicting as per the law. However, like many other medical sedatives, preparing and consuming hydroxyzine also requires a doctor’s prescription.

There are two different formula available for the preparation of the drug – the pamoate and the hydrochloride salts; and both of them are used in the medical field for the preparation of different medicines.

What Are the Ingredients of Hydroxyzine?

I am about to give you a bunch of language that only if you are a scientist will you understand. But I feel as though in order to give your pet, whom you love so much, a medication, you should first and foremost know what is in the medication because you, yourself, would not take or give your child a medication without first knowing what was in it. So, why would you do anything less for your pets?

Talking about ingredients in hydroxyzine that exists in the form of pamoate is light yellow color and it is truly odorless. It is also soluble in water meaning that it dissolves, or at least, mostly dissolves in water.

This odorless, light yellow colored powder is made up by 1-(p-chlorobenzhydryl) 4-[2-(2-hydroxyethoxy) ethyl] diethylenediamine salt of 1,1’-methylene bis (2hydroxy-3-naphthalene carboxylic acid). Again, the average person will not understand what that means but what you should know is that hydroxyzine pamoate is only some of what is in the antihistamine portion of hydroxyzine.

With that said, when you take a form of hydroxyzine because of an allergic reaction or because of anxiety you are really taking hydroxyzine hydrochloride. Hydroxyzine hydrochloride contains inactive ingredients which include colloidal silicon dioxide, D&C yellow #10, FD&C blue #1, gelatin, magnesium stearate, pregelatinized starch, sodium lauryl sulfate, and titanium dioxide.

Again, I am not expecting the average person to understand what all this language is talking about. However, I do know that some will understand this and that is why I include it. For those average everyday people basically what you need to know is when you start mixing things together there is always a chance of a reaction taking place and this reaction in case of Hydroxyzine is a favorable and friendly one.

Clinically, hydroxyzine has a little in common with other sedatives. It does not work in the way that majority of medicines that deal with anxiety work. It calms down the brain by suppressing the activity in certain regions of the subcortical region of the central nervous system. This has also been proved and demonstrated in the laboratories.

Why for Dogs?

Naturally, after scientist found it working so well on humans they thought “hydroxyzine for pets? I wonder how well that would work?” So, they started to research it more and more and found that that hydroxyzine works great for dogs and a few other pets.

You will be amazed to know that there are all kinds of prescriptions out there that are used for both humans and animals; for instance, pets can take alieve for arthritis just the same as humans can and this is also the case with hydroxyzine.

Honestly, facts like these are sometimes just mind blowing; like how similar our bodies are to that of animals and maybe, just maybe we should thus have more of respect for animals just as our ancestries did. They definitely knew stuff that we are ignoring or simply rediscovering.

In any case, hydroxyzine has been proven to reduce anxiety, help with allergies, treat atopic dermatitis, itchiness, nausea, and skin rashes in dogs. All this being said, the efficiency of the dosage of the drug on different conditions suffered by dogs is still under question.

The scientists are still working hard to draw a graph between dosage and effectiveness for hydroxyzine. Although we are not clear on the efficiency, but we are pretty clear on the fact that it is safe to use the drugs containing hydroxyzine on pets.

How ironic is it that one pill can help cure the same issues in both humans and dogs?

How Does Hydroxyzine Help with Allergies?

We the humans, and canines have a similar receptor called the H1 which is the receptor that pops up and says ‘Howdy mate’ when you are having an allergic reaction. It then allows histamine to be released into your body causing you or your beloved canine to have an allergic reaction to whatever it is we are allergic to.

The quantity of histamine related to the volume of allergy causing substance and is not directly under our control. The whole purpose of H1 receptor is to make sure that the body is suffering an allergy and that that something or some actions needs to be taken to stop the suffering.

So, what does hydroxyzine do to help with this reaction? Hydroxyzine when induced in the body, binds to the H1 receptors. By the hydroxyzine binding to the H1 receptor, it stops the receptor from signaling histamine to be released.

As a result, histamine does not release. Once the histamine that is being released is stopped then the allergic reaction stops. For instance, if you love your furry friend and know that it is going to have an allergic reaction, feed him a hydroxyzine to prevent you from having an allergic reaction.

How Does Hydroxyzine Help with Atopic Dermatitis?

If you have a canine that has atopic dermatitis than you already know that this is more than likely very irritating to them and could be potentially be painful for them. For those of you who do not have a canine with atopic dermatitis, it is when a canine has inflammation of the skin, redness, itchiness, and cracking of the skin.

In fact, canines have been known to itch the inflamed spot so bad that it either starts bleeding or has fluid coming out of the spot. This rigorous itching might not even stop after the dog has been diagnosed. As a result, the pet is always in an uncomfortable position and can even develop infection due to open wounds.

So, how to cure your dog? Dogs usually develop this condition because they have a bad diet and therefore, most of the dogs get relief after their diet has been modified. However, the root cause in many cases is hard to find and in majority of cases, even if the root cause has been found, modifying the diet can be useless or a mere temporary solution.

Luckily, it has been found that hydroxyzine can act as a first-line treatment for canine atopic dermatitis. Studies have proven that hydroxyzine is better than any other medicine or remedy.

The explanation of using hydroxyzine for treating atopic dermatitis lies in the fact that redness and inflammation of the skin are the signs that histamines are being released in the body. Which means that in order to cure your dog, the first plan of action includes stopping histamine which is definitely the job of hydroxyzine.

How Does Hydroxyzine Help with Anxiety?

Using any sedative on animals including hydroxyzine is rather a controversial topic. Hydroxyzine veterinary medicine is usually not recommended by the physicians for treating pets because there is no direct verbal feedback from the receptor and the effect and efficiency of the drug is questionable. However, experiments have shown that dogs with anxiety issues usually calm down after a dosage or two of hydroxyzine rich drugs.

Since it has been proven that the effect of hydroxyzine on animals is similar to that on humans and medical labs have already proved that this drug is safe for humans, scientists believe that the same might hold true for canines as well.

How Does Hydroxyzine Help with Itchiness?

Pruritus or as the common language calls it general itchiness can be caused by several factors. Unluckily, pin pointing the cause is such cases is simply impossible. The reasons vary from dog to dog and the living conditions around them. For example, some dogs develop itch because of parasitic organisms on them while others might be just allergic to certain plants.

Regardless of the cause, the symptoms are quite similar and must be treated. Many studies have been carried out to check the effect of hydroxyzine on the pets and interestingly all of them proved that this drug has a positive effect on the itching condition faced by canines.

Hydroxyzine significantly reduces scratching, licking and chewing behavior that the dogs develop in an attempt to fight off the itch. The studies also suggest that using hydroxyzine in short term itchiness is as effective as using it for itch that your dog has been facing from several months.

How Does Hydroxyzine Help with Rashes on Skin?

Most of the canines, at least once in a life time develop skin rashes which are marked by lesions, bumps, redness, wounds and so on. Studies prove that hydroxyzine is an excellent solution to these skin rashes. However, there is a strange fact related to the time at which hydroxyzine should be given to dogs.

Canines that have been administered with hydroxyzine before they come in contact with rash inducing agent are much more comfortable than with the ones who are fed hydroxyzine after they have been in contact with a rash inducing stimuli. This being considered, hydroxyzine consumed pre-contact or post-contact is still the best medicine to help your dog fight the skin rashes easily.

What makes use of hydroxyzine more favorable is the fact that skin rashes are usually followed by itching which can cause a severe damage to the canine and since hydroxyzine takes care of rashes as well as itch and therefore it is better than any other medicine.

What Are the Side Effects of Hydroxyzine in Canines?

What everybody has to keep in mind is the fact that when scientists start mixing chemicals together to have solutions to our diseases or to our reactions such as allergy ones, there are potential side effects too.

However, part of being responsible is knowing what the potential side effects are of any drug that you, your loved one, or your pet is taking. Hence, I am about to give you and explain to you what some potential side effects of hydroxyzine in dogs are.

Your beloved pet who has never showed any type of aggression, can turn aggressive by taking hydroxyzine. Another side effect which is a terrifying one is apnea. Apnea is when your dog stops breathing while he or she is sleeping for long periods of time. Obviously if your dog is doing this you might want to ask your veterinarian to take them off of hydroxyzine.

Your pet can also go into coma, start vomiting, have a rapid pulse, or start to twitch. Again, if your pet starts doing any of these weird things and they are using hydroxyzine, your best bet is to take them to the vet immediately.

Believe it or not but dogs can also have a loss of coordination, become depressed, or become drowsy. I know you are probably thinking how can this be? How can my dog, who is my pet, actually become depressed? But it is true. Remember we are all animals, meaning we are all connected in some way to each other which in turn means there is no reason why dogs cannot become depressed just as humans do.

Another big thing that all pet owners need to be aware of is the link in hydroxyzine weight loss and dosage. That is correct, if not given in correct dosage, your pet could start losing weight at a quick rate meaning they would be losing weight in a non-healthy way.

As you can see there are many side effects to hydroxyzine. However, what you have to keep in mind is that the side effects are better than not having your pet alive at all. So, it is your responsibility to get in touch and stay in touch with the veterinarian while your pet is taking hydroxyzine or for that matter, any medicine.

You need to keep your vet informed about any difference in behavior you have seen in your pet so that if there are any changes in your dog, it can be handled appropriately. Especially if it is aggression. You do not want your dog to attack someone just because of a drug he was on. Keep the communication line open between you and your vet.

What Research Has Been Done?

Remember that the FDA approved hydroxyzine for human consumption back in the 1950’s. However, it was not until 1989 that research even began on hydroxyzine consumption. Since 1989 there has been much research done on hydroxyzine for dogs and it has been proven to be acceptable for their consumption.

In 1989 a skin test was done using hydroxyzine on dogs. Scientist purposely infected dogs with fleas in hopes of an allergic reaction and once the dogs had an allergic reaction they immediately injected them with the hydroxyzine compound. Once injected the reaction stopped and the fleas were gone for 9 days. This was the start of hydroxyzine usage in dogs.

In 1995 an additional study was done on atopic dermatitis in dogs and the usage of hydroxyzine. The study found that hydroxyzine helped with the management of pruritus. So, when the dog had an allergic reaction or an irritation, hydroxyzine was found to help stop the irritation.

After 1995 researches progressed quickly. There was a research done in 1999, 2002, 2004, 2012, and the most recently in 2013. As the research has progressed so has its findings. I believe that research is going to continue on hydroxyzine usage for dogs.

I mean we started only knowing that dogs had somewhat of a reaction to the hydroxyzine applied to them to now knowing it can help with so many other things that it would be crazy for research not to continue.

What Hydroxyzine Dosage is Safe for Your Dog?

One way to avoid your pet having any side effects is by knowing what is the safest dosage for dogs. I mean really, how many times do you take something home from the pharmacy and cannot remember what the doctor said and cannot find the correct dosage on the bottle and guess the dosage yourself?

I hope your answer is never. So, why would you do anything less for your pet? That is why I have chosen to put the safest dosage for your beloved pet in this particular article. Everybody deserves to know how to take care of their pet to the best of their ability.

One thing that is good is that it does not seem to matter if the hydroxyzine dosage for dogs is administered orally or by intravenously, the response of the drug is quick and same. The dose for dogs is about 2mg per kg which means that if your dog weighs 5 KGs. you would give your dog 10 mg of hydroxyzine.

What If Overdose Happen?

Overdoses can cause major problems with dogs that is why it is so important for you, as the owner, to get the dosage correct. I hate to keep repeating myself but this is serious business so again, you would not overdose yourself or your loved one, so why take the chance with your pet? Avoid the overdose reactions and get the dosage correct the first time.

Overdoses could cause sedation and hypotension in your pets. Hypotension is where blood pressure goes down low which in turn can cause your dog to be lethargic. Meaning your dog may not want to do anything if you have accidentally overdosed them.

If you, by accident, overdose your pet with hydroxyzine, your pet’s stomach might have to be pumped and you might have to start thinking about supportive care. This is hard to believe but things can go so wrong that you might even have to consider life support system.

Video: Hydroxyzine-HCL – Treating My Dog’s Allergies | Veterinary Medicine

Click here to see video.


My conclusion can be broken down into 4 different parts and in simple terms easy for everybody to understand. I have done the research and can understand it to a point that I can easily relay it to you. So be prepared to find out why hydroxyzine is the best for your dog when they are having a reaction.

  1. Hydroxyzine is made of many different types of chemicals that have been proven to help fight off bad reactions that occur in both human bodies and canine bodies. What’s more is it can be done in a semi safe manner.
  2. Everything has side effects in today’s age. I mean the vegetables that we grow ourselves are not good for us anymore. I find it kind of ironic that you can literally find anything you want to know about in a push of a button and you can find it to fit your lifestyle.
    Your wants and your needs. Basically, you can find something to prove your point of view no matter what your point is. Hence, do not always pay attention to the fine print. You need to be aware of the side effects but just because there are side effects, does not mean that your pet will have them.
  3. You need to know why your pet is having to take this prescription. It is most definitely not the prescription you want to deal with in a negative way but the reason why they were prescribed a certain dosage. It is important for you to remember the correct amount of hydroxyzine for dogs dosage. You do not want to overdose your pet. Be smart and know the correct dosage for your dog.
  4. If you mistakenly overdose your pet, you could in turn be saying goodbye to your bust companion you can have here on this earth. Seriously, overdosing is no joke and even if it was an accident, your dog could have to be highly sedated or he would become hypotension. Take good care of him in this case because he should not be the one suffering so much because of your fault.

If you’re interested in reading similar articles, here’s good one on Best Glucosamine for Dogs. We’ve also posted a good guide Best Low Sodium Dog Food.