Temozolomide is an anti-cancer ("antineoplastic" or "cytotoxic") chemotherapy drug. this medication is classified as an "alkylating agent." treatment of anaplastic astrocytoma, glioblastoma multiforme (gbm) (types of brain tumors). This medication is given in a capsule form by mouth. Capsules come in 5 mg, 20 mg, 100 mg, 250 mg, sizes. your health care provider will calculate your daily dosage for you (the combination and number of each pill size.)