About this medicine
Ondansetron blocks serotonin 5-HT3 receptors involved in nausea and vomiting. Its licensed uses include sickness associated with cancer treatment and surgery. Use for nausea during weight-loss treatment is off-label. A prescriber must assess the cause of the symptoms and decide whether this is appropriate; an assessment does not guarantee a prescription.
Pack and price
8mg tablets, 10 tablets. The current catalogue price is shown separately. Generic manufacturers and inactive ingredients can differ. Read the leaflet supplied with your medicine.
How to take it
Follow your own prescription label. We do not apply another pharmacy's dose schedule to your treatment. Do not share tablets, take additional doses or repeat a course without advice.
Warnings and interactions
Do not take ondansetron with apomorphine. Tell the prescriber about heart rhythm problems, low potassium or magnesium, liver disease, bowel obstruction or severe constipation. Mention all medicines, particularly antidepressants, medicines affecting heart rhythm, tramadol and epilepsy treatments. Seek specific advice if pregnant, planning pregnancy or breastfeeding; the reference leaflet warns against use in the first trimester and breastfeeding during treatment.
Side effects and urgent help
Headache, constipation and flushing can occur. Severe allergic symptoms, fainting, an irregular heartbeat or chest pain need urgent medical attention. Persistent severe abdominal pain or inability to keep fluids down should be assessed rather than masked with anti-sickness medicine. Call 999 for a life-threatening emergency or NHS 111 for urgent advice.
Further information
This information is not a complete list of cautions or a personalised prescription. The prescriber-led pathway remains subject to clinical approval. No automatic add-on or repeat supply is offered.