Gemcitabin is A nucleoside Analog used As chemotherapy. gemcitabine is An Anti-cancer ("antineoplastic" or "cytotoxic") Chemotherapy Drug. Gemcitabine is Classified as An Antimetabolite. Gemcitabin Used for Treating Certain types of Cancer Including Cancers of the Ovary, Lungs Pancreas and Breast. Gemcitabine May Be Used Alone or with Other cancer Medicines. Gemcitabine is An Antimetabolite. It Works By Preventing Certain Proteins from Being Made that are Necessary for Tumor Growth. What Gemcitabine is Used For: Pancreas Cancer, Non-small Cell Lung Cancer, Bladder Cancer, Soft-tissue Sarcoma, Metastatic Breast Cancer, Ovarian Cancer.