Tegafur/gimeracil/oteracil

Tegafur/gimeracil/oteracil is a combination drug used in the treatment of certain types of cancer, particularly colorectal cancer. It is marketed under various brand names, including S-1 and Teysuno.

Composition

Tegafur/gimeracil/oteracil is a combination of three active ingredients: tegafur, gimeracil, and oteracil. Tegafur is a prodrug of fluorouracil, a chemotherapy medication. Gimeracil is an inhibitor of dihydropyrimidine dehydrogenase (DPD), an enzyme that breaks down fluorouracil. Oteracil is an inhibitor of orotate phosphoribosyltransferase (OPRT), an enzyme that converts fluorouracil into its active form. The combination of these three components enhances the efficacy and reduces the toxicity of fluorouracil.

Mechanism of Action

Tegafur/gimeracil/oteracil exerts its anticancer effects through the action of fluorouracil. Fluorouracil is a pyrimidine analog that interferes with DNA and RNA synthesis, leading to the inhibition of cancer cell growth. By inhibiting DPD and OPRT, gimeracil and oteracil respectively increase the concentration of fluorouracil in tumor tissues while reducing its systemic toxicity.

Indications

Tegafur/gimeracil/oteracil is primarily used in the treatment of advanced or metastatic colorectal cancer. It may also be used in combination with other chemotherapy drugs for the treatment of gastric cancer, pancreatic cancer, and other solid tumors.

Administration

Tegafur/gimeracil/oteracil is available in oral capsule form. The dosage and treatment regimen may vary depending on the specific indication and the patient's individual characteristics. It is important to follow the prescribing physician's instructions and adhere to the recommended dosage schedule.

Adverse Effects

Common side effects of tegafur/gimeracil/oteracil include nausea, vomiting, diarrhea, loss of appetite, fatigue, and hematological abnormalities such as decreased white blood cell and platelet counts. These side effects are generally manageable and reversible. However, severe adverse reactions, including allergic reactions and gastrointestinal perforation, may occur in rare cases. Patients should be closely monitored during treatment.

Contraindications

Tegafur/gimeracil/oteracil is contraindicated in individuals with a known hypersensitivity to any of its components. It should not be used in pregnant or breastfeeding women due to potential risks to the fetus or infant. Patients with severe renal or hepatic impairment may require dose adjustments or alternative treatment options.

Interactions

Tegafur/gimeracil/oteracil may interact with other medications, including certain anticoagulants, anticonvulsants, and immunosuppressants. It is important to inform the treating physician about all concomitant medications to avoid potential drug interactions.