Grastim contains Filgrastim, a recombinant human granulocyte colony-stimulating factor (G-CSF). It is used to stimulate the production of neutrophils, a type of white blood cell crucial for fighting infections, particularly in patients undergoing chemotherapy.

Uses

1. Reducing the incidence of febrile neutropenia in patients receiving myelosuppressive chemotherapy.
2. Treating neutropenia caused by bone marrow transplantation or other conditions.
3. Mobilization of peripheral blood progenitor cells (PBPCs) for collection and autologous transplantation.
4. Increasing neutrophil counts in patients with severe chronic neutropenia (SCN).

Filgrastim binds to and stimulates the G-CSF receptors on the surface of precursor cells in the bone marrow, leading to increased production, maturation, and release of neutrophils into the bloodstream.

Onset of Action - 24 to 48 hours after administration.

Duration of Action - The effect persists for about 1 to 2 weeks after the last dose.

Dosage

• Chemotherapy-induced Neutropenia: 5 mcg/kg/day subcutaneously or intravenously, starting at least 24 hours after chemotherapy.
• PBPC Mobilization: 10 mcg/kg/day subcutaneously.
• Severe Chronic Neutropenia: 6 mcg/kg/day (congenital) or 5 mcg/kg/day (cyclic).

Common Side Effects

• Bone pain
• Nausea
• Fatigue
• Headache
• Injection site reactions

Precautions

• Monitor white blood cell (WBC) counts to prevent leukocytosis.
• Use cautiously in patients with a history of splenomegaly or sickle cell disease.

Drug Interactions

• Avoid combining with lithium due to potential additive effects on neutrophil proliferation.
• Caution when used alongside antineoplastic agents as Filgrastim may alter their efficacy.

Storage

• Store between 2°C to 8°C. Avoid freezing. Protect from light.