What Is Ondansetron (Zofran)?

Potential Medication Interactions

Ondansetron is associated with nearly three hundred potential medication interactions. Patients should not use this medication during treatment with apomorphine, and it is known to interact with other serotonin 5-HT3 antagonists as well. Ondansetron can interact with a pain medication called tramadol, and it affects certain types of anticonvulsants, including phenytoin. It can interfere with antidepressants, beta-blockers, antipsychotic medicines, and drugs that reduce heart rate. Patients who take these drugs should ask their doctor whether it is safe for them to use ondansetron or whether they will need to take a different medicine. Since there are so many potential medication interactions that could occur with ondansetron, patients should ask their doctor to review their complete medication list for possible interactions before ondansetron is prescribed. They should also ask their pharmacist to double-check this list for potential issues before dispensing the drug.

Read about when doses of ondansetron need to be taken next.

When To Take Doses

Patients undergoing chemotherapy typically take one dose approximately thirty minutes before each chemotherapy session. Individuals who use ondansetron during radiation treatment are often advised to take a dose one to two hours before their appointment. When used before surgery, patients usually take it one hour before their operation. An adult dose can range from sixteen to twenty-four milligrams. Patients should read the medication label carefully before taking ondansetron. At times, patients might be asked to take their very first dose of this medicine at a clinic so they can be monitored by medical staff. The intravenous solution of ondansetron must be administered at a hospital or in a clinical setting, and patients usually receive the first dose as an infusion over a fifteen-minute period. The dose is based on the patient's weight, and doctors usually start with a dose of 0.15 milligrams per kilogram of body weight. The maximum dose for the intravenous solution is sixteen milligrams.