Certain medications can worsen Parkinson’s disease. They do so by decreasing the activity of Dopamine inside the brain.

If a patient has Parkinsonism due to the use of these medications, then the condition is called “Drug Induced Parkinsonism”.

In this condition, Amantadine may be more effective than levodopa. Anticholinergic medications (e.g. trihexyphenidyl) can also be used, but for reasons detailed in another article, I try to avoid using anticholinergics.

Medications that can produce symptoms like Parkinson’s disease

Many medications used for psychiatric problems such as schizophrenia Haloperidol, Risperidal, Olanzapine, Aripiprzole, Trifluoperazine and many more. Clozapine and Quetiapine usually do not cause problems.
Some medications for mood and depression Fluphenazine, Tranycypormine, Lithium
Some anti-nausea medications Metoclopramide, Levosulpuride, High doses of domperidone about 30-40 mg/day, Flunarazine, rarely cinnarazine
Some heart and blood pressure medications Amiodarone, methly-dopa