Febrile neutropenia (FN) following chemotherapy carries considerable patient (pt) welfare and resource use implications. It remains unclear whether cytokines commenced with antibiotic therapy hasten recovery from the septic episode.In a double blind study, 186 paediatric pts (median age 5 yrs) commencing antibiotics for FN (neutrophils ≤0.5×10 9 /1) were randomized to also receive G-CSF (Amgen) 5μg/kg/d or placebo. Study guidelines required neutrophils at least 0.2 for hospital discharge. G-CSF/placebo was stopped at withdrawal of antibiotics or if neutrophils reached 1.0. Patients received a total G-CSF dose of 603μg over 5.2 days. G-CSF treated pts had more rapid neutrophil recovery to ≥0.5 (median 3d vs 5d; P=.03; Mann-Whitney), less use of antibiotics (median 5d vs 6d; P=.02) and shorter hospital stay (median 5d vs 7d; P=.04). Fever duration (2d vs 3d) and neutrophil recovery to 0.2 (3d vs 4d) for G-CSF and placebo-treated pts respectively were not significantly different. No G-CSF-related symptomatic or haematological toxicity was seen.This study indicates that G-CSF therapy, initiated after the onset of FN in paediatric pts, accelerates neutrophil recovery and reduces the duration of both antibiotic usage and hospitalization.