My wife was taking a generic brand of benadryl (from CVS). After a couple of weeks she was breaking out in a skin rash covering 20% of her body and also tightening of the throat. The development of skin rashes and hives prompted her to take more Benadryl (thinking that this would alleviate her symptons) and the result was even more skin rashes. Skin rashes disappeared within 3 days after use of this generic brand of Benadryl ceased.