don't give him benadryl...it is an antihistamine, so you'll be giving him a double dose. Watch him carefully...if there is any sign of a stronger reaction, take him to the emergency room and call your pediatrician *immediately*.
Signs of a severe allergic reaction include swelling (particularly around the mouth and throat), wheezing, difficulty breathing, "panting": short, shallow breaths, sweating, flushing (red appearance of skin, not necessarily only on the face), itching, and hives, difficulty swallowing. There are also signs like anxiety and feelings of doom, but those would be hard to detect in a child so young. Watch for any of these symptoms. If none occur, you're likely safe...just let the antihistamine do it's job.
I'll send good thoughts your way.
at 7:58 PM on Oct. 5, 2008