Standard dose: 1 mg per pound (2.2 mg/kg), 2-3 times daily
Disclaimer: Always consult your veterinarian before giving any medication to your pet.
Diphenhydramine (Benadryl) is commonly used in dogs for allergies, insect stings, motion sickness, and mild anxiety. The standard veterinary dose is 1 mg per pound of body weight (2-4 mg/kg), given orally 2-3 times daily. Use plain Benadryl only — avoid formulations containing decongestants (pseudoephedrine), pain relievers (acetaminophen/ibuprofen), or xylitol, which are toxic to dogs. Side effects: drowsiness, dry mouth, urinary retention. Contraindications: glaucoma, cardiovascular disease, hyperthyroidism, and pregnant/nursing dogs. Benadryl is generally safe but is not effective for all types of allergic reactions. Always verify the appropriate dose with your veterinarian, especially for small breeds.