A patient is receiving chemotherapy for metastatic carcinoma. She threatens to stop her treatment because of severe nausea and vomiting. Which one of the following drugs is not likely to prevent such chemotherapy-induced nausea and vomiting?
a. Antihistamines, dronabinol, glucocorticoids, and metoclopramide have antiemetic actions that are useful in the management of vomiting caused by anticancer drugs.
b. Levodopa causes nausea because it is converted to dopamine, which activates dopamine receptors in the emetic center.