myelosuppressants

Myelosuppressants are medications that suppress bone marrow activity, leading to reduced production of red blood cells, white blood cells, and platelets. They are a broad category used primarily in cancer treatment to inhibit rapidly dividing cells, but their marrow-suppressing effect can cause immunosuppression and hematologic toxicity.

Most myelosuppressants are cytotoxic chemotherapy agents. They include alkylating agents (for example cyclophosphamide, ifosfamide), antimetabolites (such as methotrexate, 5-fluorouracil, cytarabine, gemcitabine), and platinum compounds (cisplatin, carboplatin). Other agents, including certain monoclonal antibodies and targeted therapies, can also cause bone marrow suppression as a side effect. The degree and duration of suppression depend on the drug, dose, schedule, and the patient’s marrow reserve.

Common consequences of myelosuppression are neutropenia, anemia, and thrombocytopenia. Neutropenia raises infection risk; anemia causes fatigue and dyspnea; thrombocytopenia increases bleeding risk. The nadir, or lowest point of blood counts, typically occurs days to a couple of weeks after administration and guides dose adjustments and supportive care.

Monitoring and management emphasize regular blood counts, careful dose modification, and supportive measures. Growth factors such as G-CSF or GM-CSF may reduce neutropenia, while red cell transfusions or iron management address anemia. Platelet transfusions are considered for clinically significant thrombocytopenia. Prevention of infection, bleeding, and transfusion planning are integral to care.