The US Food and Drug Administration (FDA) has approved granisetron (Kytril)
for the prevention and treatment of postoperative nausea and vomiting. The
approval was based on the results of recent clinical trials.
As a preventive antiemetic agent, granisetron was evaluated in two
randomized, double-blind, placebo-controlled trials in patients who underwent
gynecologic surgery or cholecystectomy and received general anesthesia. In one
study, patients between the ages of 18 and 88 years received a single
intravenous dose of granisetron (0.1, 1, or 3 mg) or placebo 5 minutes prior to
the induction of anesthesia. In another study, patients between the ages of 21
and 64 years received a single intravenous dose of granisetron (1 or 3 mg) or
placebo immediately before the reversal of anesthesia. In both studies,
granisetron (1 mg) was significantly more effective (P < .001) than placebo
in preventing postoperative nausea and vomiting.
As treatment of postoperative nausea and vomiting, granisetron was evaluated
in two randomized, double-blind, placebo-controlled studies in adult surgical
patients who received general anesthesia and no prophylactic antiemetic
treatment, and who experienced nausea and vomiting within 4 hours after surgery.
In one study, patients between the ages of 18 and 86 years received a single
intravenous dose of granisetron (0.1 mg, 1 mg, or 3 mg) or placebo after
experiencing postoperative vomiting or severe nausea. The study showed that
granisetron at all three doses was significantly more effective (P < .001)
than placebo in preventing further episodes of nausea and vomiting. Moreover,
the study demonstrated the agent’s efficacy when administered at intervals of
0 to 6 hours and 0 to 24 hours.
The recommended dose of granisetron is 1 mg. The most common adverse events
reported in the trials included pain, headache, and fever.
"The results of these studies are important because there is a need for
alternative therapies for postoperative nausea and vomiting," said T. J.
Gan, md, associate professor and director of clinical research, department of
anesthesiology, Duke University Medical Center. Dr. Gan said further that
patients who fail treatment with other antiemetics are subjected to extended and
unnecessary periods of nausea and vomiting, which can be severe and
debilitating. These patients may be successfully managed with granisetron.