Other Medications

Key Facts

  • Amantadine often provides immediate benefit for most PD symptoms, but its effect frequently wanes after a few weeks or months.
  • Amantadine may be particularly benefitial in people with PD who have prominent tremor or bothersome levodopa-induced dyskinesia.
  • Droxidopa is used to treat neurogenic orthostatic hypotension.

Amantadine has mildly beneficial effect in PD. Currently, its primary role is to reduce levodopa dyskinesias.


Dosages in Milligrams

Typical Treatment Regimens

Indications for Usage

Trihexyphenidyl (formerly Artane®)

2, 5

1-2 mg 2 or 3 times daily

Monotherapy or adjunct therapy, predominantly for tremor in younger people

Benztropine (Cogentin®)

0.5, 1, 2

0.5 – 2 mg 2 or 3 times daily

Same as above


Prescription Recommendations


  • Prescribe 1 tablet in the morning and then after a week, raise the dose to 1 tab twice daily.
  • You can raise dose to 1 tablet three times daily–this is the typical dose.
  • You may go as high as 5 tablets a day.
  • Most practitioners now use it later in the course of PD for dyskinesia.
  • Cannot use if poor renal function.

Side Effects

  • Redness or reddish purple discoloration of the legs, often with swelling–if it does not bother the patient you should not be worry
  • Hallucinations
  • Confusion

Ahlskog JE. Parkinson’s Disease Treatment Guide for Physicians. New York, NY: Oxford University Press; 2009.

Ahlskog JE. The Parkinson’s Disease Treatment Book: Partnering with Your Physician to Get the Most from Your Medications. New York, NY: Oxford University Press; 2005.