Ondansetron - How long does one dose work? 12hr? 24hr?

5 Nov 2009

This is taken from http://www.drugs.com/pro/ondansetron.html
"... Prevention of Nausea and Vomiting Associated With Moderately Emetogenic Cancer Chemotherapy:
The recommended adult oral dosage is one 8 mg Ondansetron hydrochloride tablet given twice a day. The first dose should be administered 30 minutes before the start of emetogenic chemotherapy, with a subsequent dose 8 hours after the first dose. One 8 mg Ondansetron hydrochloride tablet should be administered twice a day (every 12 hours) for 1 to 2 days after completion of chemotherapy."

ie. the ondansetron will wear off and you will need to continue to take it
twice a day for up to 2 days after finishing your chemotherapy.