The major types of chemotherapy drugs include alkylating agent, antimetabolites, anti-tumor antibiotics, topoisomerase inhibitors and mitotic inhibitors, states the American Cancer Society. Chemotherapy drugs are classified according to their mechanism, chemical structure and association with another drug.
Alkylating agents inhibit cellular reproduction by destroying the cell's deoxyribonucleic acid, or DNA. This group is divided into sub-classes that include nitrogen mustards, nitrosoureas, triazines and ethylenimines. Antimetabolites disrupt the formation of DNA and ribonucleic acid, or RNA, through replacement of normal DNA and RNA monomers, notes the American Cancer Society. Some antimetabolites include fluxoridine and fludarabine.
Anti-tumor antibiotics function by changing the DNA of malignant cells to prevent growth and proliferation. These drugs include anthracyclines, such as epirubicin and idarubicin. Topoisomerase inhibitors work by interrupting enzymatic activity in the DNA. Topotecan and teniposide are examples of these inhibitors. Mitotic inhibitors are generally plant alkaloids that interfere with the cell cycle.