anticholinergic drugs used in parkinsonism

Last reviewed 01/2018

The following anticholinergic drugs may be used to treat parkinsonism:

  • benzhexol hydrochloride - trihexyphenidyl is the recommended International Nonproprietary Name for this drug:
    • initial dose 1 mg daily
    • usual maintenance dose 5-15 mg in 3-4 doses

  • benztropine mesylate:
    • initial dose 0.5 mg daily
    • maximum dose usually 6 mg daily

  • biperiden:
    • initial dose 1 mg twice daily
    • usual maintenance dose 3-12 mg daily in divided doses
    • may be given as an intramuscular or slow intravenous injection

  • orphenadrine hydrochloride:
    • initial dose 150 mg in divived doses
    • maximum dose usually 400 mg daily

  • procyclidine hydrochloride:
    • initial dose 2.5 mg 3 times daily
    • maximum dose usually 30 mg daily
    • may be given by intramuscular injection in acute dystonia

Anticholinergic drugs they should not be used in patients with:

  • untreated urinary retention
  • closed angle glaucoma
  • gastointestinal obstruction