Can I Give My Dog Benadryl and If So, How Much?

Reviewed By Julie •  Updated: 06/22/20 •  8 min read
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Is Benadryl to give your dog? How much should the dose be? What side effects could my dog experience after taking Benadryl? These are great questions! If you’re asking these questions, we’ve got the answer for you in this article.

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What is Benadryl?

Benadryl, which also goes by its generic name “diphenhydramine,” is a popular over the counter medication we often associate with humans. We take this medication most often to treat seasonal allergies.

Benadryl is an antihistamine that works to reduce all types of allergic reactions caused by insect bites/stings, pollen, or even reactions to vaccines. This medication is also sometimes used as a medication to help people get to sleep or even to prevent nausea and motion sickness. Benadryl isn’t the only brand of available that offers diphenhydramine. You may also find it available under drugstore and grocery store labels, etc.

Is Benadryl Safe for my Dog?

The FDA has approved Benadryl for human use only; however, veterinarians do advise their pet parents to give it to their fur babies when warranted. This medication is safe for dogs and is usually well tolerated.

While this medication is generally safe for dogs, there are some things to consider with Benadryl and your dog:

Why is Benadryl Given to Dogs?

Some pet parents give their dogs Benadryl for different reasons including:

Allergies: this medication is safe to give a dog when they suffer an insect bite, bee/wasp sting or have allergic reactions to things in their environment, including food. However, if your pup is having an anaphylactic reaction, this is a medical emergency and Benadryl will not work in these situations. Signs your dog may be having an anaphylactic reaction include difficulty breathing and facial swelling. You’ll need to get him to the vet immediately if your fur baby’s showing these signs.

Anxiety: some pet parents have given their dogs Benadryl to help them ease travel anxiety. They may sometimes give their fur baby diphenhydramine if they’re afraid of fireworks or thunder. This medicine may also help relieve motion sickness.

However, if your dog is experiencing anxiety, it’s best to ask the vet to examine your pup and then advise what treatment may be better for him. Benadryl may not be the best way to treat anxiety and motion sickness, so always check with your vet for their advice on how to best help your fur baby. Hives: Benadryl has been shown to work well in both pet parents and their dogs when they develop hives. Hives are usually due to an allergic reaction and can be horribly itchy.

Mast cell tumors: these are white blood cells that develop in response to allergies. If your fur baby experiences a mast cell degranulation, the result is a huge release of histamine into your pup’s system. The vet may prescribe Benadryl to relieve the symptoms a massive histamine release in your fur baby. Treating heart worms: when some dogs are treated for heart worms, they may experience an allergic reaction when the heart worms die. Some vets may prescribe Benadryl to alleviate the symptoms caused by this condition.

Can I Give my Dog Benadryl for Itching?

Yes, you can give your fur baby Benadryl for itching! In fact, this is the best antihistamine for dog itching, in most cases. Benadryl is a great medication to treat all types of allergies and reactions, including flea bites, food allergies and more. In fact, this medication is most often used to treat a dog’s itchy skin.

Are there Other Antihistamine for Dog Itching?

Yes, there are alternative antihistamine medications that may be safe for your dog. However, before giving your dog any medication meant to humans, always check with your vet first. They’ll have the best advice on specific medications that are safe for your fur baby.

Some alternative antihistamines include Zyrtec (cetirizine) and Claritin (loratadine). These are most often used for allergic reactions. However, just as with Benadryl, some dogs may be allergic to these ingredients, or dogs may become hyperactive or sedated, depending on the medication.

Dog Benadryl Dosage

Vets usually advise giving dogs 1mg of Benadryl for every one pound of body weight. However, before giving your dog this medication, be sure to check with your vet for the correct dosage. In Benadryl tablets, you’ll most often find that each tablet contains 25 mg of medication. This means that if your dog is about 25 lbs, then he should be given one tablet. The dosage should be increased or decreased based on your fur baby’s size and your vet’s advice.

If you have a smaller dog, you can use Benadryl tablets made for children. These tablets some in a smaller dose. Again, always consult your vet for the right dose of this medication for your fur baby. Your fur baby can have a dose of Benadryl about every 8-12 hours, per your vet’s directions. This means your pup could have the medicine about 2-3 times a day.

What About Liquid Benadryl for Dogs?

The liquid form of Benadryl is not safe for dogs. This is because is the liquid version contains alcohol, which is poisonous for dogs.

Benadryl Dogs Overdose

Is it possible for my dog to overdose on Benadryl? The quick answer is yes. Here are the symptoms to watch for if you suspect, or know for certain, your dog has taken too much Benadryl:

As with any drug, taken in doses that are too large, Benadryl can even lead to death. So, it’s important to always check with your vet for dosing instructions, in order to avoid giving your fur baby too much medication.

Are There Some Dogs That Shouldn’t Take Benadryl?

While this medication is generally safe when given in the right dose, there are some dogs that may not tolerate Benadryl. Certain medical conditions may be worsened by diphenhydramine, or as noted earlier, this medication can also interact with other medicines your fur baby may be taking. So, always ask the vet before giving your dog Benadryl.

Dogs with these health conditions may not tolerate Benadryl:

Home Remedies for Dog Allergies

If your dog can’t tolerate Benadryl, there are some home remedies that can help to alleviate his symptoms. However, remember to call your vet is your canine companion is having a severe or anaphylactic allergic reaction—this is a medical emergency.

For allergic reactions that are not a medical emergency, you can try these home remedies:

Oatmeal bath: this can help to serve your fur baby’s itchy, irritated skin. However, be aware that some dogs are allergic to oatmeal. If you and your dog are not allergic to oatmeal, all you need to do is mmix plain oatmeal and water, and then then apply this mixture to your dog’s skin. You can also use this mix to give your pup a bath and put the oatmeal directly in the water. Your dog will need to soak for about 10 minutes in order to calm the itchiness.

You can use the plain oatmeal you have at home, or you can try Oatmeal Dog Shampoo & Conditioner to sooth your canine companion’s irritated skin.

Bovine colostrum: this is a substance found in the first milk of a mother and it works by strengthening the baby’s immune system. Colostrum contains an ingredient known as proline-rich polypeptide (PRP). This ingredient works to keep immune sells from reacting to the allergy causing substance. It’s also an anti-inflammatory that can reduce histamine.

You can find this ingredient in Allergy Relief Immune Chews for Dogs.

Quercetin: this is a phytonutrient that’s found in veggies and fruits. This antioxidant also has antihistamine and anti-inflammatory properties. It’s sometimes also referred to as “nature’s Benadryl.”

You can dry Zesty Paw Aller-Immune Broth Booster, which includes quercetin and other ingredients to help your fur baby’s allergies.

We hope this article has answered your questions about the safety of Benadryl for your dog. Remember to always consult your vet before giving your pup this or any other medication. We wish you both an allergy-free season!

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Julie is a graduate of the University of North Carolina, Wilmington, where she studied Animal science. Though contrary to the opinion of her parents she was meant to study pharmacy, but she was in love with animals especially cats. Julie currently works in an animal research institute (NGO) in California and loves spending quality time with her little cat. She has the passion for making research about animals, how they survive, their way of life among others and publishes it. Julie is also happily married with two kids.

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