Other Antimetabolites for Chemotherapy

Antimetabolites are a group of medications that simulate naturally occurring compounds that are involved in the reproduction of cells. These antimetabolites are inserted in place of the naturally occurring compound, which results in disruption of DNA, RNA, or protein synthesis. Cancer cells are generally much more rapidly dividing, so the effects are primarily felt by the cancer cells; however normal cells are also affected by this process, which is the source of many of the side effects.

Class Drugs

• 6-Mercaptopurine

• 5-Fluorouracil

• Azacitidine

• Capecitabine

• Cladribine

• Cytarabine

• Fludarabine

• Gemcitabine

Class Mechanism of Action

Generally, these antimetabolites are pyrimidine or purine analogs that disrupt DNA/RNA synthesis, which leads to death of rapidly dividing cells

Class Applications

See individual drugs

Class Adverse Effects

Myelosuppression

See individual drugs

Drug Table

Drug Name	Application	Comments	Image
6-mercaptopurine	Acute lymphoblastic leukemia	Mechanism; Converted to active form, which inhibits purine synthesis; Metabolites can also be inserted into DNA/RNA rendering the DNA/RNA non-functional; Adverse Effects; Hepatotoxicity; Myelosuppression	"Mercenary" "Captain" "Pur Water Filter"
5-fluorouracil	Solid tumors; Basal cell carcinoma (applied topically)	Mechanism; -Pyrimidine analog; Inhibits thymidylate synthase, which is used in production of thymidine; -Reduced thymidine levels inhibits DNA synthesis; -Use of leucovorin can increase effectiveness of 5-FU by improving binding the thymidylate synthase.; Adverse Effects; Mucositis; Myelosuppression	"Flu Shot" "Row" "Urine"
Azacitidine	Myelodysplastic syndrome; Acute myeloid leukemia	Mechanism; -Pyrimidine analog (cytidine); -Converted to active form, which gets inserted into RNA and inhibits RNA function; Adverse Effects; -Hepatotoxicity; -Renal Toxicity; -Tumor-lysis Syndrome; -Myelosuppression	"AZ - Arizona" "Acid"
Capecitabine	Colorectal cancer; Breast cancer (metastatic)	Mechanism; -Converted to 5-fluorouracil primarily in tumor cells (actions mostly tumor specific); -Inhibits thymidylate synthase, which is used in production of thymidine; -Reduced thymidine levels inhibits DNA synthesis; Adverse Effects; Mucositis; Myelosuppression	"Cap" "Sit" "Bean"
Cladribine	Chronic lymphocytic leukemia; Non-Hodgkin lymphoma; Hairy cell leukemia	Mechanism; -Converted to active form, and is inserted into the 3' end of DNA and inhibits elongation; -Inhibits ribonucleotide reductase and inhibits DNA repair; Adverse Effects; -Myelosuppression; -Nephrotoxic; -Malignancy; -Teratogenic	"All-Clad" "Rib" "Bean"
Cytarabine	Acute myelogenous leukemia	Mechanism; -Cytidine analog; -Inhibits DNA polymerase; -Incorporated into DNA and terminates chain elongation	"Cyborg" "Tar" "Bean"
Fludarabine	Chronic lymphocytic leukemia; Non-Hodgkin lymphoma; Hairy cell leukemia	Mechanism; Purine analog; Incorporated into DNA and RNA, which likely mediates its effects; Adverse Effects; Myelosuppression; Renal dysfunction; Tumor lysis syndrome	"Flood" "Bean"
Gemcitabine	Pancreatic cancer; Non-small cell lung cancer	Mechanism; Cytidine analog; Inhibits DNA synthesis; Adverse Effects; Myelosuppression; Renal dysfunction; Hepatotoxicity; Pulmonary Toxicity	"Gem" "Sit" "Bean"