I searched through the archives and found only one posting mentioned antihistamine. In 94, Barbara Yacos wrote "I have heard that some parkinsonians are taking the antihistamine Periactin (cyproheptadine hydrochloride) for tremor. I know Benedryl sometimes helps but Periactin is supposed to be better. Is that true?" Is there any follow up to this posting? I take actifed to cope with allergies in spring and I experienced some relaxation of rigidity (more laid back) when I am on with actifed. Since I am not sure how actifed interacts with anti-PD drugs, I don't take sinemet or deprinyl when I take actifed. Could it be that antihistamine shot down some of the brain function that restores the chemical balance of PD patient? I would also appreciate any input on the possible interaction between anti-PD and anti-allergy drugs. Thank you. Liangshiu Lee ([log in to unmask])