Zefei 1 g Injection (Gemcitabine) is a prescription chemotherapy medicine used in the treatment of a variety of solid tumors, including lung, breast, pancreatic, bladder, and ovarian cancers. Gemcitabine works by disrupting the growth and replication of cancer cells, slowing disease progression. Zefei is administered via intravenous infusion by healthcare professionals and requires ongoing medical supervision, including regular blood tests to monitor your response to treatment.