Ondansetron

Ondansetron is a medication used to prevent nausea and vomiting caused by cancer chemotherapy, radiation therapy, or surgery. It works by blocking the action of serotonin, a natural substance that may cause nausea and vomiting.

Indications

Vomiting and nausea associated with cytoxic radiotherapy & chemotherapy, prophylaxi & treatment of postoperative vomiting and nausea.

Dosage

-Chemotherapy-induced nausea and vomiting (CINV): 8 mg orally twice daily. -Radiotherapy-induced nausea and vomiting (RINV): 8 mg orally three times daily. -Postoperative nausea and vomiting (PONV): 16 mg orally one hour before anesthesia induction.

Contra-Indications

-Prevention of nausea and vomiting associated with highly emetogenic cancer chemotherapy. -Prevention of nausea and vomiting associated with radiotherapy. -Prevention and treatment of postoperative nausea and vomiting.

Special Precautions

-Use with caution in patients with hepatic impairment. -Monitor for serotonin syndrome when used with other serotonergic drugs. -Use with caution in patients with a history of QT prolongation.

Side Effects

Headache,constipation, sensation of flushing in the head and epigastrium, rarely allergic reactions.

Drug Interactions

-Apomorphine: Increased risk of profound hypotension. -Drugs affecting QT interval: Increased risk of arrhythmias. -Serotonergic drugs: Increased risk of serotonin syndrome. -CYP3A4 inducers or inhibitors may affect ondansetron metabolism.