Which medication should not be administered to a Parkinson's patient experiencing nausea?

In the context of treating nausea in a patient with Parkinson’s disease, the choice of medication is crucial due to the potential for exacerbating motor symptoms associated with the condition. Doperidol, an antipsychotic that is part of the butyrophenone class, is primarily used for its antiemetic properties. However, it has been associated with the exacerbation of Parkinsonian symptoms because it can block dopamine receptors. Since Parkinson’s disease is characterized by a deficiency of dopamine, any medication that further blocks dopamine can worsen the motor control issues that these patients face.

In contrast, medications like ondansetron, prochlorperazine, and metoclopramide, while also having potential side effects, do not specifically have the same risk of worsening Parkinsonian symptoms as doperidol. Ondansetron is a 5-HT3 receptor antagonist that does not interact with dopamine pathways as significantly. Prochlorperazine, while a phenothiazine, has a lesser impact on dopamine pathways compared to doperidol. Metoclopramide can have some effects on dopamine, but its primary action is more gastroprokinetic, which can be beneficial in patients with nausea.

Choosing doperidol for a patient with Parkinson's is