Browse Prescribing Notes by Therapeutic Subcategory

ALKYLATING AGENTS
There are five major types of alkylating agents: nitrogen mustards (eg, Mustargen, Cytoxan, Ifex), ethyleneimines (eg, Hexalen, Thioplex), alkyl sulfonates (eg, Myleran), nitrosoureas (eg, BCNU, Zanosar), and triazenes (eg, DTIC). The chemotherapeutic and cytotoxic effects are due to the alkylation of DNA which disturbs DNA synthesis and cell division; the ultimate cause of cell death related to DNA is unknown. Methylhydrazines (eg, Matulane) and platinum complexes (eg, Platinol, Eloxatin, Paraplatin) do not directly alkylate DNA; they form covalent adducts with DNA. Emcyt is a combination of estradiol coupled to normustine by a carbamate link; it binds to β-tubulin and microtubule-associated proteins, causing microtubule disassembly and antimitotic actions.
Cancer cells with mutant or absent tumor suppressor protein p53 do not suspend cell-cycle progression or undergo apoptosis and exhibit resistance to treatment. Resistance also develops rapidly when treated with a single agent. Bifunctional agents (eg, nitrogen mustards, nitrosoureas) are predominately cytotoxic, and monofunctional methylating agents (eg, Matulane, Temodar) have a greater capacity for mutagenesis and carcinogenesis. Mechlorethamine and nitrosoureas have strong vesicant properties; use with caution.