OBJECT DRUGS

Dopamine Agonists:

• Bromocriptine (Parlodel, etc.)
• Cabergoline (Dostinex)
• Levodopa (Dopar)
• Pramipexole (Mirapex, etc.)
• Ropinirole (Requip, etc.)

PRECIPITANT DRUGS

Dopamine Antagonists:

• Haloperidol (Haldol)
• Metoclopramide (Reglan, etc.)
• Phenothiazines
• Thiothixene (Navane)

Comment:

Dopamine agonists, used for Parkinson's disease and other disorders, may be inhibited by dopamine antagonists resulting in a worsening of Parkinsonism. Conversely, the therapeutic effect of dopamine antagonists would be expected to be reduced by dopamine agonists.

Class 2: Use Only if Benefit Felt to Outweigh Risk

• Use Alternative:
• Antipsychotics: Atypical antipsychotics such as clozapine (Clozaril), olanzapine (Zyprexa), quetiapine (Seroquel), and risperidone (Risperdal) are less likely to produce extrapyramidal side effects. Theoretically, they would be less likely than butyrophenones, phenothiazines, or thioxanthines to inhibit dopamine agonists.
• Monitor: Be alert for a reduction in efficacy of both dopamine agonists and dopamine antagonists if they are coadministered.