Gemcitabine, sold under the brand name Gemzar, among others, is a chemotherapy medication used to treat a number of types of cancer. These cancers include testicular cancer,breast cancer, ovarian cancer, non-small cell lung cancer, pancreatic cancer, and bladder cancer. It is given by slow injection into a vein.Common side effects include bone marrow suppression, liver and kidney problems, nausea, fever, rash, shortness of breath, mouth sores, diarrhea, neuropathy, and hair loss. Use during pregnancy will likely result in harm to the baby. Gemcitabine is in the nucleoside analog family of medication. It works by blocking the creation of new DNA, which results in cell death.Gemcitabine was patented in 1983 and was approved for medical use in 1995. Generic versions were introduced in Europe in 2009 and in the US in 2010. It is on the World Health Organization's List of Essential Medicines.