Benadryl is a popular treatment for dogs that suffer from allergies and travel sickness. The drug was originally developed as an antihistamine for humans, but it was found to have several useful side effects and many people now use it to treat dogs for the same conditions humans suffer from. read more
Benadryl poisoning is uncommon, normally Benadryl is dosed at 1mg/lb twice per day; some side effects (not overdose) of Benadryl include lethargy and a loss of appetite. Overdose symptoms include abnormal heart rate, vomiting, diarrhoea, seizures, aggression or depression. read more