Diphenhydramine (Benadryl) dosing for dogs is typically 1 mg per pound of body weight, given 2–3 times daily. For a 15-pound dog, this translates to approximately 15 mg per dose. However, you should always consult your veterinarian before giving any medication to your dog, as they can assess your pet's specific health status, current medications, and the reason for treatment to provide safe, personalized guidance.
Veterinary-strength formulations and over-the-counter products may have different concentrations, and using the wrong product or dosage could be harmful. Additionally, Benadryl is not appropriate for all dogs or all situations—certain health conditions, ages, or drug interactions may make it unsafe. A vet can also confirm whether antihistamines are the best treatment option for your dog's symptoms, or recommend alternatives.
Never exceed the recommended dose or frequency without veterinary approval, and watch for side effects such as drowsiness, dry mouth, or urinary retention. If your dog has an allergic reaction, injury, or medical emergency, seek immediate veterinary care rather than relying solely on over-the-counter medications.