Information about Ondansetron

Ondansetron Uses

Ondansetron is used to prevent nausea and vomiting.

How Ondansetron works

Ondansetron is an antiemetic medication. It works by blocking the action of a chemical messenger (serotonin) in the brain that may cause nausea and vomiting during anti-cancer treatment (chemotherapy) or after surgery.

Common side effects of Ondansetron

Fatigue, Headache, Constipation, Diarrhea, Hypoxia (decreased oxygen level in blood)
Written By
Reviewed By
MD (Pharmacology), MBBS
Last updated:
11 Mar 2020 | 10:28 AM (UTC)
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Available Medicine for Ondansetron

OndemAlkem Laboratories Ltd
13 to ₹1087 variant(s)
VomikindMankind Pharma Ltd
11 to ₹1519 variant(s)
EmesetCipla Ltd
25 to ₹2618 variant(s)
PerisetIpca Laboratories Ltd
12 to ₹746 variant(s)
ZoferSun Pharmaceutical Industries Ltd
12 to ₹1087 variant(s)
EmigoZuventus Healthcare Ltd
12 to ₹535 variant(s)
EmefilmDelvin Formulations Pvt Ltd
286 to ₹3302 variant(s)
EternaBlue Cross Laboratories Ltd
29 to ₹323 variant(s)
IsvGalpha Laboratories Ltd
11 to ₹473 variant(s)
OndamacMacleods Pharmaceuticals Pvt Ltd
15 to ₹473 variant(s)

Expert advice for Ondansetron

  • You have been prescribed Ondansetron for prevention of nausea and vomiting caused after surgery or due to chemotherapy and radiotherapy.
  • Unlike some other nausea medicines, the side effects for Ondansetron are relatively mild.
  • It comes in many different forms that do not need to be swallowed, such as a film that is placed on  the tongue or as a dissolving pill.
  • It is fast-acting and starts working within 30 minutes.
  • If you vomit within one hour of taking a dose, take another dose.
  • Avoid heavy meals and try eating small nourishing snacks throughout the day. Also, sip water regularly to help avoid dehydration.

Frequently asked questions for Ondansetron


Q. How quickly does Ondansetron work?

Ondansetron starts working within half an hour to 2 hours. It dissolves rapidly into the bloodstream and starts showing its effect.

Q. What are the side effects of Ondansetron?

The most common side effects of Ondansetron are constipation, diarrhea, fatigue and headache. However, these are usually not bothersome and resolve on their own after some time. Consult your doctor if these persist or worry you.

Q. When should you take Ondansetron?

Ondansetron should be taken with a full glass of water, with or without food. It should be used exactly as per the dose and duration advised by the doctor. Usually, the first dose of Ondansetron is taken before the start of your surgery, chemotherapy or radiation treatment.

Q. Is Ondansetron a steroid?

No, Ondansetron is an antiemetic and not a steroid. Ondansetron is a selective 5-HT3 receptor antagonist. It is prescribed for the prevention and treatment of nausea and vomiting which is commonly observed after surgery or due to cancer chemotherapy.

Q. Does Ondansetron work for seasickness?

No, Ondansetron does not work for seasickness. This is because Ondansetron has very little effect on the nausea associated with motion sickness.


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