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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