Antihistamine
Benadryl Dosage for Dogs
Calculate the safe Benadryl (Diphenhydramine HCL) dose for your dog based on weight. Adjust the slider below for instant results.
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About Benadryl for Dogs
Benadryl (generic name: Diphenhydramine HCL) is an over-the-counter medication in the Antihistamine category. It is commonly used for dogs to treat:
- Allergic reactions
- Itchiness
- Mild sedation
- Insect stings
- Hives
Dosing Notes
1 mg per pound of body weight. Liquid: 1 ml per 2.5 lbs.
Warnings & Contraindications
Warnings
- Use only plain diphenhydramine — avoid combination products with decongestants or pain relievers
- May cause drowsiness, dry mouth, or urinary retention
Do NOT Use If
- Do not use in pets with glaucoma, high blood pressure, or cardiovascular disease without vet approval
Important Notes
- Always verify the product contains ONLY diphenhydramine as the active ingredient
Benadryl Dosage Chart for Dogs
| Weight | Dose (mg) | Frequency |
|---|---|---|
| 5 lbs | 5 mg | Every 8 hours as needed |
| 10 lbs | 10 mg | Every 8 hours as needed |
| 20 lbs | 20 mg | Every 8 hours as needed |
| 30 lbs | 30 mg | Every 8 hours as needed |
| 40 lbs | 40 mg | Every 8 hours as needed |
| 50 lbs | 50 mg | Every 8 hours as needed |
| 60 lbs | 60 mg | Every 8 hours as needed |
| 80 lbs | 80 mg | Every 8 hours as needed |
| 100 lbs | 100 mg | Every 8 hours as needed |
40 lb Dog
Benadryl Dose
Generally safe for dogs at this dose
40mg
💊
Tablet Form
1.5 × 25 mg tablets
💧
Liquid Form
16.0 ml (3.2 tsp)
🕐
Frequency
Every 8 hours as needed
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Always consult your veterinarian before giving any medication to your pet. These dosages are general guidelines. Individual pets may require different dosing.