Stability of Carmustine for Topical Application

To the Editor.—  Applied topically, carmustine (a nitrosourea compound) is an effective treatment of the cutaneous lymphoma, mycosis fungoides.¹ Because this therapy is usually a long-term, outpatient treatment procedure, the possibility that pharmacist or patient mishandling might affect the stability of carmustine, a compound that is intrinsically unstable because of the "N-nitroso" moiety, has caused concern among dermatologists.² In older protocols, patients were given bulk powder and instructions for making up the solutions at home. This procedure has obvious shortcomings; it would be preferable if the pharmacist could make up the alcohol solution of carmustine. This study was conducted to evaluate the stability of carmustine for the period that might pass between pharmacist preparation and patient use.For total-body application, carmustine is dissolved in alcohol (usually 95% ethanol) and diluted with tap water to obtain a final concentration of approximately 10 mg/60 mL of a 10% alcohol solution.