Generic Zofran® | Emeset (Ondansetron) - 4mg (10 Tablets)

How does Generic Zofran (Ondansetron) work?

Zofran tablets, syrup and injection all contain the active ingredient ondansetron hydrochloride dihydrate, which is a type of medicine called a 5HT3 antagonist. (NB. Ondansetron is also available without a brand name, ie as the generic medicine.) Ondansetron is used to prevent and treat nausea and vomiting that can be caused by chemotherapy or radiotherapy treatment for cancer, or by surgery.

Vomiting is controlled by an area of the brain called the vomiting centre. The vomiting centre is responsible for causing feelings of sickness (nausea) and for the vomiting reflex. It is activated when it receives nerve messages from another area of the brain called the chemoreceptor trigger zone (CTZ) and when it receives nerve messages from the gut.

Chemotherapy, radiotherapy and surgery can cause a substance called serotonin (5HT) to be released in the gut. This 5HT acts on the 5HT3 receptors that are found in the gut and causes nerve messages to be sent to the vomiting centre.

5HT released by chemotherapy, radiotherapy and surgery also activates the 5HT3 receptors that are found in the CTZ in the brain, causing further messages to be sent to the vomiting centre.

Ondansetron works by blocking the 5HT3 receptors that are found in the brain and gut. This prevents the nausea messages being sent from these areas to the vomiting centre. Ondansetron therefore prevents nausea, retching and vomiting that can otherwise occur following surgery or due to cancer treatments.

Ondansetron can be given by mouth (Zofran tablets or syrup), by injection into a muscle or vein, by drip into a vein (intravenous infusion), or by suppository (see the Zofran suppositories factsheet linked at the end of this factsheet).

What is Generic Zofran (Ondansetron) used for?

• Preventing and treating nausea and vomiting caused by chemotherapy or radiotherapy for cancer
• Preventing and treating nausea and vomiting following surgery.

Generic Zofran (Ondansetron) Side Effects

• Headache
• Constipation
• Flushing
• Hiccups
• Allergy to active ingredient (hypersensitivity)
• Involuntary movements
• Alteration in results of liver function tests
• Low blood pressure (hypotension)
• Chest pain
• Slow heart rate (bradycardia)
• Abnormal heart beats (arrhythmias)
• Seizures