Should i take benadryl (diphenhydramine hcl) for my poison ivy even though i suffer from anxiety?

Other antihistamine: The main reason to take antihistamines for poison ivy is to decrease the itching. There is risk of central nervous system effects with benadryl (diphenhydramine). Potentially it could aggravate anxiety disorders. An antihistamine that does not cross over into the brain like Benadryl (diphenhydramine) is Allegra (fexofenadine). It will still help with the itching.