From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
Zofran (ondansetron) should be taken for short periods, usually 1-2 days for nausea and vomiting due to chemotherapy, radiation, or surgery, though it may be used for up to 5 days in some cases, under medical supervision due to potential side effects like headaches, constipation, and rarely, heart rhythm abnormalities, as reported in a study published in 2013 1.
Key Considerations
- The medication works by blocking serotonin receptors in the brain and gut that trigger nausea.
- For chemotherapy patients, it's often prescribed 30 minutes before treatment and then for 1-2 days afterward.
- For postoperative nausea, it's usually given as a single dose.
- Extended use beyond these timeframes should only occur under medical supervision.
Potential Side Effects
- Headaches
- Constipation
- Rarely, heart rhythm abnormalities, such as QT interval prolongation, as warned by the US Food and Drug Administration 1.
Important Notes
- If you need anti-nausea medication for longer periods, your doctor may recommend alternating with other medications or exploring underlying causes of persistent nausea.
- Always follow your healthcare provider's specific instructions regarding duration of use for your particular situation.
- The safety and efficacy of ondansetron have been established in various studies, including a meta-analysis published in 1992 2, which compared ondansetron to metoclopramide in the prevention of chemotherapy-induced nausea and vomiting.