Benadryl® – is a popular allergy and itch medicine for adults and children.

The good news: It’s also OK to give to dogs.

Can a dog have Benadryl®? Yes!

In the proper dosage, Benadryl is safe for dogs and can help relieve:

  1. dog allergies
  2. the after-effects of vaccinations
  3. reactions to flea bites, bee stings or hornet and wasp stings
  4. ‘hot spots’ on the skin or itching
  5. motion sickness for dogs – so it’s perfect for that long car ride
  6. sometimes your Vet may recommend a daily low-dosage to treat anxiety problems


The active ingredient in Benadryl is diphenhydramine.

Always check with your Vet

Although many websites recommend Benadryl as an important part of your dog first aid kit, others say you should ask your Vet before you give it to your pet.  So why not make this a must-ask at your next Vet appointment and get your Vet’s advice on when and how much Benadryl to give, should the need ever arise.

Benadryl dosage for dogs

The rule of thumb for Benadryl for dogs, is 1 mg, per pound of the dog, every 8 hours.  However, Benadryl comes in tablet form, in a 25 mg dosage. For a small dog like a Morkie you might need just 4 or 5 mg and it would  be impossible to accurately divide a pill into 5 pieces…. So the liquid form is recommended

Children’s BENADRYL® Liquid does not contain any dyes or alcohol and can be accurately measured with a special eyedropper or syringe without the needle.

For dogs under 10 pounds:    ½ tsp. (2.5 mL) every 4 to 6 hours

For dogs over 10 pounds:   1 tsp. (5 mL) every 4 to 6 hours

To measure accurately, get an eye dropper, or syringe without the needle, with measurement markings.

Here’s a handy Benadryl dosage chart for dogs, that you can download free


Benadryl dosage chart

Do NOT use these types of Benadryl

They are not safe for your dog.

Generic or no-name Benadryl

Benadryl tablets

Congestion Relief

Sugar-free Benadryl

Children's Cough Relief

Side effects of Benadryl

Your dog will get sleepy and may be more thirsty than normal.  Some food before the Benadryl is a good idea. Other less-common possible side effects include:

  • vomiting
  • diarrhea
  • loss of appetite
  • hyperexcitability
  • sedation effect

Do Not Use Benadryl IF:

  • your Morkie has:
    • hyperthyroidism
    • glaucoma
    • high blood pressure
    • chronic lung disease
    • bladder disorders
  • your dog is on other medications
  • your Morkie is under 4 months old
  • your dog is pregnant or nursing

Use these only - Children's Genuine Benadryl liquid

These packages are all sugar-free, children’s liquid Benadryl


This site provides general information and should not be considered medical advice. You should always check with your Veterinarian prior to choosing a treatment option for your pet.


BENADRYL® is a registered trademark of Johnson & Johnson