The medicine is used to treat certain types of cancer such as gastrointestinal stromal tumors, acute lymphocytic leukemia, and chronic myeloid leukemia. It comes in the group of medicine called tyrosine kinase inhibitors. Imatinib 400 mg is taken with or without food at the same time every day. The common side effects associated with the medicine include vomiting, nausea, abdominal pain, diarrhea, edema, and rash. Do not use medicine in case of pregnancy and breastfeeding.