Secondary prophylactic administration of recombinant human granulocyte colony stimulating factor (G-CSF) following an episode of febrile neutropenia is recommended if maintenance of dose-intensity is desired. This policy was adopted in our center in patients treated with an intent for cure or durable complete response. The purpose of this study was to evaluate the safety and feasibility of this policy. Patients in whom neutropenia was associated with a life-threatening infection and those who developed prolonged myelosuppression were excluded. Fifty-one patients who developed febrile neutropenia that required intravenous antibiotics following moderately myelotoxic chemotherapy were included. These patients received the next cycle of the same chemotherapy regime without dose modification but with the support of filgrastim (300 or 480 mg/d sc for at least 10 consecutive days). Diagnoses included lymphoma (n = 19), breast cancer (n = 15), germ cell tumor (n = 7), small-cell lung cancer (n = 5), and other solid tumors (n = 5). The incidence of febrile neutropenia during the first cycle given with filgrastim support (N1) was 8/51 (16%). Intravenous antibiotics were required for 3-7 d (median, 4.5 d). During the following cycle (N2), febrile neutropenia developed in 4/41 (10%) patients. Intravenous antibiotics were given for 2, 4, 5, and 7 d. Other dose-limiting toxicities developed in 1/51 patients who received N1 and in 1/41 patients who received N2. There was no drug-related death associated with either cycle. In conclusion, a policy of full-dose chemotherapy with secondary G-CSF support in patients who develop febrile neutropenia following moderately myelotoxic chemotherapy is relatively safe and feasible.