API Capecitabine

Capecitabine More Info

Capecitabine is a chemotherapy drug.

1. Chemical and Pharmacological Properties

Chemically, capecitabine is a fluoropyrimidine carbamate. It is a prodrug, which means it is inactive in its original form and needs to be metabolized in the body to become active. The active metabolites of capecitabine interfere with the synthesis of DNA and RNA. By inhibiting thymidylate synthase, an enzyme essential for the production of thymidine, which is a building block of DNA, it disrupts the normal cell division process. This effect is more pronounced in rapidly dividing cancer cells than in normal cells.

2. Medical Uses

Cancer Treatment: It is widely used in the treatment of various cancers. For example, in breast cancer, it can be used as part of adjuvant therapy (therapy given after the primary treatment such as surgery to reduce the risk of cancer recurrence). In metastatic breast cancer, capecitabine can be used alone or in combination with other drugs like docetaxel. In colorectal cancer, it is an important drug for the treatment of advanced disease. It can be used in combination with oxaliplatin in the treatment of metastatic colorectal cancer.

Dosage and Administration: The dosage of capecitabine varies depending on the type of cancer, the patient's body surface area, and other factors. It is usually taken orally in the form of tablets. The dosing schedule is typically designed to maintain a certain level of the active drug in the body over a period of time. For example, in a typical colorectal cancer treatment regimen, it might be taken twice a day for a 14 - day period, followed by a 7 - day rest period, and this cycle is repeated.

3. Side Effects

Gastrointestinal Tract: One of the most common side effects is related to the gastrointestinal system. Patients may experience nausea, vomiting, diarrhea, and stomatitis (inflammation of the mouth and lips). Diarrhea can be severe in some cases and may require dose adjustments or supportive treatment such as fluid and electrolyte replacement.

Hematological Effects: It can also cause myelosuppression, leading to a decrease in blood cell counts. This may result in anemia (low red blood cell count), leukopenia (low white blood cell count), and thrombocytopenia (low platelet count). A low white blood cell count increases the risk of infections, and a low platelet count can lead to an increased risk of bleeding.

Hand - Foot Syndrome: Another characteristic side effect is hand - foot syndrome. This is manifested as redness, swelling, pain, and sometimes blistering on the palms of the hands and soles of the feet. It is caused by the drug's effect on the skin cells in these areas, which are actively dividing cells similar to cancer cells.

4. Precautions and Contraindications

Capecitabine should be used with caution in patients with pre - existing gastrointestinal disorders such as severe ulcerative colitis or Crohn's disease, as it may exacerbate these conditions. Patients with a history of severe bone marrow suppression or certain blood disorders may also require careful monitoring. It is contraindicated in patients who have a known hypersensitivity to capecitabine or any of its components. Pregnant and breastfeeding women are generally advised against using capecitabine due to the potential harm to the fetus or infant.