ABSTRACT

This chapter presents classification & mode of action, indications & dermatological uses, formulations/presentation, dosages & suggested regimens, baseline investigations, considerations & monitoring, contraindications, cautions, important drug interactions, adverse effects & their management, use in special situations, essential patient information of Azathioprine. The synthetic purine analogue azathioprine (AZA) was initially developed as an immunosuppressant in the 1960s, but is most widely prescribed for its anti-inflammatory actions, especially in the treatment of skin and bowel disease and lupus. AZA is a pro-drug and after oral ingestion and absorption it is rapidly hydrolysed non-enzymatically to an imidazole derivative and 6-mercaptopurine. Tests to measure thiopurine methyltransferase activity are widely available and play a key role in the safe and effective prescribing of AZA. AZA has also been widely used as a steroid-sparing treatment for bullous pemphigoid and in this context appears to have similar efficacy to mycophenolate mofetil.