How Much Benadryl Can I Give My Dog?

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how much Benadryl can I give my dog

Giving your dog Benadryl 2-3 times per day will make him feel better. Make sure there are 8-12 hours apart.

For example, if your dog weighs 40 pounds, you should give him 40 mg up to 3 times a day.

But Benadryl comes in many forms. Read further and learn more about each type of Benadryl and the risks of overdosing your dog with it.

What Is Benadryl?

Diphenhydramine, also known under the brand name Benadryl, is an antihistamine that helps both dogs and humans with allergies, anxiety and motion sickness, and cough.

Benadryl is not FDA-approved for dogs or other animals. Luckily, you can give it to your dog ONLY with approval from your vet.

Can Dogs Have Benadryl? What Does Benadryl Treat in Dogs?

In general, people use Benadryl for treating mild to moderate allergies. However, Benadryl is good for other allergic reactions such as:

  • Coughing
  • Sneezing
  • Anaphylactic reaction
  • Hives
  • Swelling
  • Inflammation
  • Redness
  • Runny nose and eyes

It can also be used for:

  • Anxiety
  • Motion sickness
  • Snake and insect bites
  • Treatment of mast cells tumors

When to Ask Your Vet About Benadryl?

Don’t give your dog Benadryl without asking your vet! Dogs react differently and this could be fatal for them.

If you notice any allergic reaction, consult your veterinarian first or visit a veterinary hospital.

Depending on symptoms, they will recommend you the correct dosage of Benadryl, if that’s the case. However, they might decide to give your dog natural alternatives to Benadryl.

Side Effects

dog itches

Sure, the correct Benadryl dosage won’t hurt your dog. But what if your dog is allergic to Benadryl itself?

Allergy symptoms

  • Red rashes on the skin
  • Skin chewing or licking
  • Swelling of the face and tongue
  • Diarrhea
  • Upset stomach
  • Vomiting

Common side effects of Benadryl

  • Hypersalivation
  • Dry mouth
  • Rapid breathing
  • Increased heart rate
  • Sleepiness
  • Urinary retention

Uncommon side effects of Benadryl

  • Vomiting
  • Decreased appetite
  • Increased appetite
  • Diarrhea

Benadryl Overdose. First signs

If you think your dog has a diphenhydramine overdose, call your vet immediately! There are some signs to keep an eye on. Some common signs for Benadryl overdose are:

  • Agitation
  • Rapid heartbeat
  • Rapid breathing
  • Dilated pupils
  • Constipation
  • Seizures
  • Hyperactivity or depression
  • Excessive salivating
  • Slow, shallow or stopped breathing

How Much Benadryl Can I Give My Dog? Benadryl Dosage For Your Dog

As a rule of thumb, the general dosage for dogs is 1 mg of Benadryl for every one pound of your dog’s body weight.

Benadryl comes in many forms.  Let’s talk a little about every type:

  • Liquid: Because it includes alcohol, this form is dangerous for dogs and you should not give it to them. Instead, the Children’s liquid formula is a safer option.
  • Tablet: Each Benadryl tablet includes 25 mg of Diphenhydramine (1 tablet for a 25-pound dog), but always check the label. Never assume that all products will have the same dosage.
  • Topical: When applying this form of benadryl to your dog’s skin, test a small area first and make sure there isn’t any allergic reaction. Never apply gel or cream to your dog’s skin if it’s blistering. Don’t treat your dog’s benadryl allergy with benadryl! You might overdose it and make it worse.
  • Injection: The injectable Benadryl is available in 10 mg/ml and 50 mg/ml.

Again, talk to your veterinarian and let him decide whether giving your dog Benadryl is the best idea or not.

When Is Benadryl Bad For Your Dog?

There are some situations when giving Benadryl to your dog is not the best idea. Another reason to contact your vet first!

I will list some examples where Benadryl could be fatal for your dog:

Medical conditions. There are some medical conditions such as heart disease or high blood pressure, that in combination with Benadryl could make it worse.

Allergic reaction. Dogs can have an allergic reaction to Benadryl too! That’s why you must talk to your veterinarian before giving it to your dog.

Side effects. Sedation is the most frequent, although dogs might also have changes in their respiration, heart rate, and urination. Some may vomit or have diarrhea on rare occasions.

Different formulas or products. Acetaminophen and pseudoephedrine are not safe for dogs, even though they are used in certain allergy medicines.

Overdose. An overdose is incredibly dangerous. If your dog takes too much Benadryl, contact an emergency veterinarian or the poison control hotline at (888) 426-4435 immediately.

Dilated pupils, constipation, fast heartbeat, behavioral abnormalities, and seizures are all signs of an overdose.

Pregnant or nursing. Give your pregnant dogs or nursing Benadryl ONLY if your vet said so!

Alternatives to Benadryl

If your dog has allergies to dust, pollen, or other things that they may track in from outside the house, make sure you wash your dog’s bedding on a regular basis and keep your home clean.

Make sure your pet has occasional baths, as your vet recommends, in order to keep allergies away from your dog’s coat.

If you don’t want to give your dog Benadryl, you might want to switch to CBD. [1]

Researches show that CBD can help with inflammation and allergies. Natural CBD chews and CBD oil for dogs are some good natural alternatives.

Colostrum is another option that treats your dog from allergies. It is a supplement that improves your dog’s immune system and protects him from bacteria, viruses, and fungi.

Baking Soda is the easiest and fastest way to calm your dog’s itchy or red skin.  Simply mix baking soda with a little bit of water. Place the paste on the affected area for a few hours, then wash it.

How Often Can You Give a Dog Benadryl?

Veterinarians suggest up to 3 times a day, depending on your dog’s body weight.  Small dogs under 25 pounds can take the children’s liquid formula.

It is better at giving your puppies the exact amount of Benadryl than giving them tablets. This way you also avoid overdosing.

Risks Of Benadryl For Dogs

Make sure that the Benadryl you’re giving your dog contains only Diphenhydramine. It should not be combined with other drugs such as Tylenol as it can cause harmful side effects.

Carefully weigh your dog and give him Benadryl according to his weight. Giving your dog too much Benadryl might cause him serious health problems.

The Bottom Line

Benadryl is safe as long as you give your dog the exact amount that’s needed, according to your veterinarian.

Always check if there are any adverse reactions after you gave your dog Benadryl.

However, there are more ways for treating your dog’s allergies such as CBD oil, Colostrum, and Baking Soda.

Ask your vet if you are not sure which treatment is the best one for your dog.

Photo of author
Andrei Bratu
Andrei is the owner of Dog Food Camp and manages the team of expert writers on the site. He is passionate about helping dog lovers learn about canine nutrition.

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