Amgen's Neupogen: Information for patients, doctors, and healthcare professionals about Neupogen. It is used for treating neutropenia, a common side effect of chemotherapy.DrugDigest: Filgastim ( Neupogen ): Information on dosage, usage, side effects, interactions, and drug comparisons including generics when available.Neupogen: a.k.a. Filgastim, G-CSF.Neupogen: Full prescribing information from RxList.