Anonymouscat (Sarasota, Florida) on 07/04/2012:

Took Benadryl for hives, but begain having serious adverse side effects: pounding, irregular or racing heartbeat shaking tremors difficult time catching your breathe, my tongue felt thick. Seriously feel like I was going to die! Well all of that happened to me, dr called and said she thought it was a reaction from the Benadryl. So I took some activated charcoal tablets I always keep on hand, and the adverse side effects fell away It was truly AMAZING.