Oncopen contains Ondansetron, a medicine primarily used to prevent and treat nausea and vomiting caused by cancer chemotherapy, radiation therapy, or surgery. It is especially effective in managing chemotherapy-induced nausea and vomiting (CINV) and is widely used in cancer and surgical care.

Mechanism of Action
Ondansetron works by blocking serotonin (5-HT3) receptors in the gut and the brain. During cancer treatments or surgery, serotonin is released from cells in the small intestine, triggering a signal to the brain that causes nausea and vomiting. By preventing serotonin from binding to its receptors, Ondansetron helps stop this signal, reducing the urge to vomit.

Uses
Oncopen is commonly used for:

• Prevention and treatment of nausea and vomiting during chemotherapy or radiotherapy

• Control of post-operative nausea and vomiting

• Occasionally used off-label for gastroenteritis-related nausea or morning sickness in pregnancy, under a doctor’s supervision

  Adverse Effects
  Ondansetron is usually well tolerated, but possible side effects include:

  • Headache

  • Constipation

  • Dizziness or light-headedness

  • Rarely, it may cause heart rhythm disturbances such as QT prolongation, especially in patients with pre-existing heart conditions

  • In very rare cases, allergic reactions, including rash, itching, or swelling