Chemotherapy is the use of drugs to kill cancer and is a commonly used mode of treatment for a variety of cancers. There are many different types of chemotherapy medications, and not all of them are used for every cancer. Medications may be grouped according to their mechanism of action, or they may be grouped because they were made from the same source, like plants, according to the American Cancer Society. Many times more than one drug will be used to achieve the most optimal results.
Anti-tumor Antibiotics
Drugs that are anthracyclines are considered anti-tumor antibiotics, and they interfere with cancer cells' replication of DNA, preventing them from multiplying, according to the American Cancer Society (ACS). Anthracycline drugs include doxorubicin, daunorubicin, epirubicin and idarubicin. Other drugs that are anti-tumor antibiotics that are not anthracyclines include actinomycin-D, bleomycin and mitoxantrone.
Alkylating Agents
Alkylating drugs damage DNA of cells, which keeps cancer cells from replicating and multiplying. These drugs also have the possibility of causing leukemia after chemotherapy due to the damage to DNA, which also damages bone marrow. The risk of leukemia depends on the amount of alkylating drugs given, according to the ACS. Drugs in this category include nitrogen mustards like cyclophosphamide and ifosphamide; nitrosoureas like carmustine; alkyl sulfonates like busulfan; and triazines like dacarbazine. Sometimes the platinum chemotherapy drugs like cisplatin and carboplatin are grouped with the alkylating agents because they work similarly.
Antimetabolites
Antimetabolites are made of compounds that resemble existing substances in regular cells, according to the Cleveland Clinic Cancer Center. These drugs interfere with the growth of DNA and RNA. Drugs in this class include 5-fluorouracil, gemcitabine, methotrexate and cytarabine.
Mitotic Inhibitors
Plant alkaloids and other drugs made from natural sources make up many drugs in this category, and these drugs kill cancer cells by stopping the production of proteins needed for cell reproduction, according to the ACS. Mitotic inhibitors include taxanes like paclitaxel, vinblastine and vincristine, and estramustine.
Topoisomerase Inhibitors
Topoisomerases are enzymes that help strands of DNA separate in order to be copied, and these drugs interfere with these enzymes, preventing reproduction of cells. Drugs in this category include topotecan, irinotecan, etoposide and teniposide. Some of these drugs can increase the risk of a second cancer (leukemia), according to the ACS.
