HYDROXYUREA
Primary site of action is enzyme ribonucleoside diphosphate reductase. The drug is specific for S phase of the cell cycle and causes cell to arrest at the G1-S interface.Chronic myeloid leukaemia. Solid tumours.
Chronic myeloid leukaemia: 20-30 mg/kg/day in single doses. Solid tumours: 80 mg/kg as a single dose every 3rd day.
Marked bone marrow depression, severe anaemia, pregnancy, lactation.
Periodic hematological monitoring, renal & hepatic fumction monitoring; recent radiotherapy or cytotoxic therapy; elderly & children.
Bone marrow suppression, including megaloblastic changes. Erythema caused by irradiation may be exacerbated by hydroxyurea. Gastrointestinal disturbances, impairment of renal function, pulmonary oedema, mild dermatological reactions, alopecia, and neurological reactions.
Risk of hematological toxicity increased with concomitant use of cytarabine. Immunization with live, attenuated vaccines can result in manifestations of infection in patients on cytotoxic drugs. CNS depressants enhance the drowsiness side effect of hydroxyurea.
