Antihistmine OD =============== þ Physostigmine - does little, per Dr. Krenzelok - others say it works fine, and more recent papers show this: þ Benadryl - main problem with Benadryl OD isn't the anticholinergic effects. some say - diphenydramine (Benadryl) known to have effects on sodium channels; in very big doses, acts like TCA OD -- prolonged QT intervals, tachycardia, arrhythmias, vascular collapse, seizures - may give a bit of a benzo prophylactially (1-2 mg for adult) along with physostigmine