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Pet Medication 101: Benadryl

Estimated Reading Time 2 minutes
Pet Medication 101: Benadryl

It’s important to understand a medication’s uses and side effects before giving it to your pet. This medication info sheet is meant to give you a good understanding of what Benadryl (diphenhydramine) is used for, how it works, and potential side effects in cats and dogs. Always consult a veterinarian before giving your pet any medication.

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1. Drug Name:

diphenhydramine

2. Common Name or Brand Name(s):

Benadryl

3. How Dispensed:

Over-the-counter and prescription

4. Forms:

capsule, liquid, injectable, shampoo, topical spray. Multiple strengths are available so be sure to read the label carefully.

5. Drug Type/Class:

Antihistamine

6. Uses for Cats and Dogs:

Motion sickness, sedation, anaphylaxis and allergic reactions, atopy, mast cell tumors

7. How it Works:

Diphenhydramine is a first-generation antihistamine. It competitively inhibits H1 receptors, blocking the action of histamine, a substance in the body that is responsible for allergic symptoms.

8. Side Effects and/or Signs of Overdose:

Excessive sleepiness, dry mouth, urine retention. May causes excitement, especially in cats.

9. Drug Interactions:

Can cause excessive sleepiness when use with depressant drugs.

10. Cautionary Statements:

Diphenhydramine is generally safe to use under the direction of a veterinarian. Do not use in pets with glaucoma, hyperthyroidism, hypertension, seizure disorders, heart disease, or in neonates.

Read more:

How to Give Your Dog Oral Medication

How to Give Your Cat Oral Medication

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Published: 4/22/2021
Last updated: 8/29/2021

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