irinotekan

Irinotecan is a chemotherapy drug used to treat certain types of cancer. It belongs to a class of drugs called topoisomerase inhibitors, which work by interfering with the enzymes that cancer cells need to divide and grow. Specifically, irinotecan inhibits topoisomerase I, an enzyme that plays a crucial role in DNA replication and repair. By blocking this enzyme, irinotecan causes damage to the DNA of cancer cells, leading to their death.

It is most commonly prescribed for metastatic colorectal cancer, often in combination with other chemotherapy agents like fluorouracil and leucovorin. It has also been investigated and used for other cancers, including pancreatic cancer and small cell lung cancer. The drug is administered intravenously, typically over a specific period of time.

The effectiveness of irinotecan can vary depending on the type and stage of cancer, as well as individual patient factors. Like most chemotherapy drugs, it can cause side effects. Common side effects include diarrhea, nausea, vomiting, bone marrow suppression (leading to a decrease in white blood cells, red blood cells, and platelets), and hair loss. Diarrhea can be particularly severe and requires careful management. Other potential side effects may include fatigue and loss of appetite. Dosage adjustments and supportive care are often necessary to manage these side effects. Irinotecan is metabolized in the liver, and its effectiveness and toxicity can be influenced by genetic factors, particularly related to UGT1A1 enzyme activity, which can affect how the drug is broken down in the body.