Orphenadrine (sold under many brand names)[1] is an anticholinergic drug of the ethanolamine antihistamine class; it is closely related to diphenhydramine.

[6] Although orphenadrine and other anticholinergics have largely been superseded by other drugs; they have a use in alleviating motor function symptoms, and appear to help about 20% of people with Parkinson's.

Common side effects include dry mouth, dizziness, drowsiness, constipation, urine retention, blurred vision, and headache.

[8] Continuous and/or cumulative use of anticholinergic medications, including first-generation antihistamines, is associated with higher risk of cognitive decline and dementia in older people.

[9][10] Orphenadrine is known to have these pharmacological properties: George Rieveschl was a professor of chemistry at the University of Cincinnati and led a research program working on antihistamines.