Browse Prescribing Notes by Therapeutic Subcategory

Antimetabolites inhibit RNA and DNA function and prevent cells from carrying out vital functions essential for cell growth and survival. They are partially selective for tumor cells and are toxic to most rapidly dividing normal cells (eg, bone marrow). Antifolates inhibit dihydrofolate reductase (DHFR) which depletes tetrahydrofolate cofactors needed for purine and pyrimidine synthesis and are most effective when cells are rapidly proliferating. Fluoropyrimidines and purine analogs inhibit the formation of precursors needed for the synthesis of DNA. Cytidine and adenosine nucleoside analogs become incorporated into DNA and block its further elongation and function. Acquired resistance may be an obstacle with many of these agents.