Can my Dog Eat Piriton?

Written by: Jamie
Updated: March 10, 2020

If your dog has allergies, you might be wondering “can my dog eat Piriton?” Here we look at whether Piriton is safe and how you should approach dosage.

can dogs eat piriton

Does your dog suffer from allergies? If so, you might be wondering whether human antihistamine tablets would be a suitable solution.

Lots of people whose pets have allergic reactions wonder whether Piriton could be the answer to their problems.

However, Piriton is a human medication, so is it suitable to give to dogs or could it be harmful? 

Although Piriton is designed for use in humans, it is sometimes prescribed by vets to help control dog pollen allergies.

There are some other allergy symptoms which can also be relieved in dogs by using Piriton including:

  • Scratching
  • Itching
  • Irritated eyes
  • Runny nose

These symptoms are usually caused by one or more of the following conditions:

  • Skin allergy
  • Hayfever
  • Hypersensitivity to dust mites
  • Wasp or bee stings
  • Fleas

Dog and vet

What is Piriton?

Piriton is a sedating anti-histamine which contains the active ingredient Chlorphenamine.

The body naturally produces histamine, however, when dogs (or humans) have an allergy, a huge amount of histamine is produced in reaction to the substance.

The immune system goes into overdrive and this produces a range of irritating symptoms that are linked with allergies.

Piriton’s active ingredient Chlorphenamine blocks the histamine reaction and reduces the chance of symptoms developing while relieving the itching linked with allergies.

Is Piriton Safe for Dogs?

In most cases, yes, Piriton is safe for dogs. However, it should only be used on the advice of your vet. Dogs can have adverse reactions to medication just like we do.

Harrier dog standing against white background

Piriton Dose For Dogs

Usually, a vet will prescribe Piriton for your dog. They will bear in mind the weight and age of your pet together with the severity of the symptoms that they are experiencing in order to determine the most appropriate dosage.

Dogs who have many symptoms will usually need a large dose of Piriton than a pet who simply scratches compulsively.

Usually, the Piriton dosage for dogs will range from 0.2mg up to 0.4mg per kilo of their body weight, and the dose will be repeated every 8 to 12 hours to achieve maximum results.

So for example, a Piriton dose for a 20kg dog would be between 4mg and 8mg (or 1-2 tablets) every 8 hours or so.

The tablets (the same which we take) usually come in 4mg doses. This is about the same as 10ml of the liquid version.

Generally, speaking a 1/2 tablet dosage is about right for smaller breeds and 1-2 tablets should suffice for larger breeds.

Like with us humans, these doses can be repeated up to three times per day. Depending on how effective the Piriton is being. It’s important to monitor your dog’s condition and only administer the allergy pills when needed.

Let’s just reiterate that you should consult your vet first before administering anything though.

adorable dog

How Long Will Piriton Take To Work In Dogs?

Within the first 24 hours of administering Piriton to your pet, you should start to see some improvements in their symptoms.

Your pet may feel slightly drowsy after being given Piriton, however, this is normal.

Recommended: Don’t miss our guide to non-pull harnesses next

Does Piriton Produce Side Effects?

Since Piriton is a sedative antihistamine, it can produce a few side effects in dogs. These can include:

  • Vomiting and nausea – many dogs who are given Piriton experience vomiting or nausea.
  • Poor appetite – dogs often have a gastric response which leads to them losing their appetite or changing their eating habits.
  • Constipation or diarrhea – Piriton may have an effect on your pet’s bowel movements. Usually, constipation is more common than diarrhea, however, you should observe your pet’s elimination habits and stools to see if your pet is experiencing a problem.
  • Excessive thirst – Piriton sometimes causes too little saliva to be produced by the salivary glands. The result is a dry mouth with affected pets appearing to be extremely thirsty and needing to drink a lot more water. Signs to look out for that indicate your pet’s mouth is dry is closing and opening of the mouth as well as lip-smacking.
  • Behavior changes – dogs who are taking Piriton sometimes change their behavior. Sleeping habits are especially affected. Some pets struggle to sleep during the night however others become especially drowsy and lethargic. Some may even become more aggressive.

sick dog


What to Be Aware of When Giving Piriton to a Dog

Although Piriton is safe for dogs, you shouldn’t just give Piriton tablets to your pet without consulting your vet first.

This is because your pet should be thoroughly examined by a professional to determine whether or not their symptoms are a result of an allergic reaction or whether they are caused by some other health problem.

It is also important for a vet to prescribe the most appropriate dose of Piriton to give your pet maximum relief without an overdose.

Dogs can overdose on Piriton, and therefore it’s very important to only give your pet the recommended amount.

The maximum amount which can be prescribed is 1.1mg per pound of your pet’s body weight. An overdose can result in a very severe reaction including seizures. Therefore, it’s vital to talk to your vet before you give your pet Piriton.

Some dogs experience adverse reactions to Piriton’s active ingredient, Chlorphenamine Maleate.

These adverse reactions could even be life-threatening. Not only that but if your pet is also taking other medications, they could experience a negative reaction when taking Piriton in conjunction with their existing medicine.

Your vet will be able to advise you whether there is likely to be a negative reaction between Piriton and your pet’s existing medication.

If your pet manifests any symptoms like fluid retention, persistent vomiting, or vision problems after taking Piriton, stop using it immediately and seek veterinary assistance.

Dog looking through a flap

Piriton For Wasp and Bee Stings

If your pet is stung by a wasp or bee, it’s likely that they won’t have a serious reaction.

Most dogs find being stung just an annoyance, however, in some cases there can be an allergic reaction, characterized by irritation and redness or swelling of the muzzle or face.

In these situations, Piriton tablets for dogs provide quick relief.

Piriton For Fleas Bites

Flea bites sometimes cause allergic reactions in dogs because of the saliva which they inject under the skin.

As a result, their skin can become inflamed and itchy, and the more your pet scratches at their skin, the worse the problem becomes with infection and hair loss occurring.

Although using regular flea treatments to help prevent the problem in the first place is essential, should your pet be affected by an allergic reaction to a bite, Piriton can help to bring them relief.

Recommended Next: Curious about Victorian Bulldogs? Check out our latest guide to this awesome breed.

Stopping Allergies in Dogs With Piriton

Although Piriton is generally safe for most dogs to use, it’s important to only give it to your pet under the guidance of your vet.

This will ensure that the chances of a negative reaction are minimal and that your pet experiences maximum relief from their unpleasant allergic symptoms.

Make sure to follow us on social media to be notified of new articles here at!

About the Author

Hi, I'm Jamie! I've always been around dogs and now writing about them is an absolute joy.
Read more about my story here.
Reach me at or connect with me on LinkedIn below.

Share your thoughts

Your email address will not be published. Required fields are marked

{"email":"Email address invalid","url":"Website address invalid","required":"Required field missing"}