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.
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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