AbstractCyclophosphamide is a chemotherapeutic agent which was first discovered in experimental tumours in rats, and it has since been widely used to treat malignancies and severe manifestations of various auto‐immune diseases. High‐dose chemotherapy and continuous daily oral regimens are associated with significant toxicity profiles, but i.v. pulsed regimens have lowered the rates of adverse effects in rheumatological studies. Cyclophosphamide has been shown to be useful in the treatment of severe autoimmune conditions due to its powerful immunosuppressive ability; however, it remains a relatively underused modality in dermatology. This article reviews the current literature on cyclophosphamide and its clinical applications in dermatology.