High versus low dose granisetron, a selective 5HT3 antagonist, for the prevention of chemotherapy-induced nausea and vomiting.

Fifty six patients, with histologically confirmed cancer, who received highly emetogenic chemotherapy, were entered on a randomized double blind, low versus high dose, study of granisetron, a 5HT3 receptor antagonist. A single dose of intravenous granisetron protected the majority of patients from nausea and vomiting, 160 micrograms/kg was more effective than 40 micrograms/kg with no more side effects. Additional doses of granisetron conferred added benefit to patients who experienced breakthrough symptoms. Granisetron at a dose range of 40-240 micrograms/kg over a 24 hour period was well tolerated with the only side effect being mild headache.