title: Effect of anticholinergic agents upon acquired nystagmus: a double-blind study of trihexyphenidyl and tridihexethyl chloride.
abstract: We conducted a randomized, double-blind, crossover trial of two anticholinergic agents--trihexyphenidyl and tridihexethyl chloride (a quaternary anticholinergic that does not cross the blood-brain barrier)--in patients with acquired nystagmus and measured visual acuity and nystagmus before and at the end of 1 month on each medication. Of the 10 patients admitted to the study, only five completed trials of both drugs due to intolerance of medication or intercurrent illness. Of six patients who completed the trial of trihexyphenidyl, only one showed improvement. Of six patients who completed a trial of tridihexethyl chloride, four showed improvement. We conclude that (1) trihexyphenidyl is not a reliable treatment for acquired nystagmus, although occasional patients may benefit; (2) anticholinergic agents may suppress nystagmus by peripheral rather than central mechanisms; and (3) the side effects of anticholinergic agents limit their effectiveness in the treatment of nystagmus.
authors.affiliation: Department of Neurology, University Hospitals, Cleveland, OH 44106.
authors.forename: R J
authors.initials: RJ
authors.lastname: Leigh
authors.forename: T H
authors.initials: TH
authors.lastname: Burnstine
authors.forename: R L
authors.initials: RL
authors.lastname: Ruff
authors.forename: R J
authors.initials: RJ
authors.lastname: Kasmer
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009759:Nystagmus, Pathologic / Q000188:drug therapy*; D010276:Parasympatholytics / Q000627:therapeutic use*; D000644:Quaternary Ammonium Compounds / Q000627:therapeutic use*; D014282:Trihexyphenidyl / Q000627:therapeutic use*; D014792:Visual Acuity / Q000187:drug effects
chemical_list: D010276:Parasympatholytics; D000644:Quaternary Ammonium Compounds; D014282:Trihexyphenidyl; C005386:tridihexethyl