tablet contains the active constituent is Gefitinib, which is given to treat some kind of lung cancer (non-small cell), breast cancer, white blood cells cancer and other kind of cancers. In cancer, cells in the body grow and multiply in a way that is `out of control`. Chemotherapy (anti-cancer) medicines work by inhibiting the way cells grow and increase in number. Gefitinib belongs to a group of anti-cancer medicines known as tyrosine kinase inhibitors. ©