Question

A patient undergoing chemotherapy was given an antiemetic, after which he developed symptoms like acute dystonia, bradykinesia, and tremors. Which of the following drugs would have caused these symptoms?

• A. Ondansetron
• B. Metoclopramide
• C. Meclizine
• D. Scopolamine

Answer 1

The Correct Option is B

To determine which drug caused symptoms like acute dystonia, bradykinesia, and tremors, we need to understand that these are extrapyramidal side effects. These side effects are often associated with certain medications that block dopamine receptors, particularly those that act centrally in the brain. Of the given options, Metoclopramide is known to have this effect.

Explanation:

• Ondansetron: This is a 5-HT₃ receptor antagonist used to prevent nausea and vomiting. It does not cause extrapyramidal symptoms.
• Metoclopramide: This drug is a dopamine receptor antagonist. It can cross the blood-brain barrier and block dopamine receptors in the central nervous system, leading to extrapyramidal symptoms such as dystonia, bradykinesia, and tremors.
• Meclizine: An antihistamine used to treat motion sickness and vertigo. It does not commonly cause extrapyramidal symptoms.
• Scopolamine: An anticholinergic used for nausea and motion sickness. It also does not cause such symptoms.

Therefore, the symptoms experienced by the patient are most likely due to Metoclopramide.