DRUG CLASS AND MECHANISM: Cyclophosphamide is a drug that is used primarily for treating several types of cancer. In order to work, cyclophosphamide first is converted by the liver into two chemicals, acrolein and phosphoramide. Acrolein and phosphoramide are the active compounds, and they slow the growth of cancer cells by interfering with the actions of deoxyribonucleic acid (DNA) within the cancerous cells. It is, therefore, referred to as a cytotoxic drug. Unfortunately, normal cells ... are affected, and this results in serious side effects. Cytoxan also suppresses the immune system and is also referred to as immunosuppressive.