Drug of choice for neutropenia due to cancer chemotherapy is :
**Core Concept**
Neutropenia is a condition characterized by a low count of neutrophils, a type of white blood cell that plays a crucial role in fighting infections. In cancer patients undergoing chemotherapy, neutropenia is a common side effect that increases the risk of infections. The drug of choice for managing neutropenia in this context is a medication that stimulates the production of neutrophils or reduces the risk of infections.
**Why the Correct Answer is Right**
The correct answer is Filgrastim (G-CSF), a recombinant human granulocyte colony-stimulating factor (G-CSF) that stimulates the production of neutrophils in the bone marrow. Filgrastim works by binding to G-CSF receptors on the surface of hematopoietic cells, leading to an increase in the production of neutrophils and a subsequent increase in their count in the blood. This medication is commonly used in cancer patients undergoing chemotherapy to reduce the risk of infections and neutropenia.
**Why Each Wrong Option is Incorrect**
**Option A:** Epoetin alfa, a recombinant human erythropoietin, is used to stimulate the production of red blood cells, not neutrophils. It is used to treat anemia in cancer patients, not neutropenia.
**Option B:** Lenalidomide is an immunomodulatory medication used to treat multiple myeloma and myelodysplastic syndromes, but it is not the drug of choice for neutropenia in cancer patients.
**Option C:** Darbepoetin alfa is another erythropoiesis-stimulating protein used to treat anemia in cancer patients, but it is not used to treat neutropenia.
**Clinical Pearl / High-Yield Fact**
It's essential to note that Filgrastim (G-CSF) should be used in conjunction with other supportive care measures, such as antibiotics and antifungal agents, to manage neutropenia in cancer patients.
**Correct Answer:** C. Filgrastim (G-CSF)