Paradoxical Excitation Associated with Diphenhydramine (Benadryl)

Did the patient show agitation, excitation or psychiatric symptoms shortly after the dose was taken?

Is there another explanation (mental illness, stimulant drug use, etc) that can explain the reaction?

Does the patient have a history of poor response to tricyclic antidepressants or antipsychotic agents?

Has the patient had a toxic reaction to synthetic opioid analgesics taken at a regular dose?