Imatinib is a protein-tyrosine kinase inhibitor drug that inhibits the BCR-ABL tyrosine kinase, the constitutive abnormal tyrosine kinase created by the Philadelphia chromosome abnormality in CML. Imatinib mesylate is the active ingredient in medicine, and the inactive ingredients are colloidal silicon dioxide, crospovidone, hydroxypropyl methylcellulose, magnesium stearate, and microcrystalline cellulose. The usage of Imatinib recommended by healthcare professionals is Chronic Myelogenous Leukemia, Acute Lymphocytic Leukemia, Philadelphia Chromosome-Positive, Gastrointestinal Stromal Tumors, Hypereosinophilic Syndrome, Chronic Eosinophilic Leukemia, Systemic Mastocytosis, and Myelodysplastic Syndrome. This drug comes as tablets in 100 mg and 400 mg to administer orally via the mouth. Imatinib tablets should be administered once daily, whereas a dose of Imatinib 800 mg should be administered as Imatinib 400 mg twice daily.