Doksorubitsiin

Doksorubitsiin, known in English as doxorubicin, is an anthracycline antibiotic used in cancer chemotherapy. It is a cytotoxic agent derived from the soil bacterium Streptomyces peucetius. Its mechanism involves intercalation into DNA, inhibition of the enzyme topoisomerase II, and generation of reactive oxygen species, leading to DNA damage and apoptosis in rapidly dividing cancer cells.

Doksorubitsiin is used to treat a range of solid tumors and blood cancers, including breast cancer, non-Hodgkin lymphomas, leukemias, sarcomas, ovarian cancer, and bladder cancer. It is typically given intravenously as part of combination regimens; a liposomal formulation exists to modify distribution and reduce some toxicities. Dosing is based on body surface area and prior therapy, and regimens vary by cancer type. The drug may cause red-orange urine, tears, and sweat during treatment.

Administration and pharmacokinetics: Doksorubitsiin is administered intravenously, with careful monitoring for infusion reactions and the risk of extravasation. It is extensively metabolized in the liver and excreted mainly in bile; the elimination half-life can be prolonged after repeated courses. Because of potential cumulative cardiac toxicity, clinicians monitor cardiac function and impose lifetime dose limits (commonly around 450–550 mg/m2 for conventional doxorubicin). Dexrazoxane can be used as a cardioprotective agent in selected patients.

Side effects and safety: Common adverse effects include bone marrow suppression, nausea, vomiting, mucositis, alopecia, and fatigue. Cardiotoxicity is a major long-term risk and can lead to congestive heart failure, occasionally developing months or years after treatment. Liposomal forms may have different toxicity profiles, such as reduced cardiotoxicity but increased risk of hand–foot syndrome. Doksorubitsiin is teratogenic and contraindicated in pregnancy; fertility effects may occur.