Symptoms of gastrointestinal toxicity most often develop within the first several weeks of therapy with Azathioprine tablets and are reversible upon discontinuation of the drug. The reaction can recur within hours after rechallenge with a single dose of Azathioprine tablets. Azathioprine induced liver cirrhosis: An unusual side effect Author Aida Ben Slama Trabelsi, Eya Hamami, Mehdi Ksiaa, Ahlem Souguir, Mohamed Ben Mabrouk, Ahlem Brahem, Ali Jmaa, Salem Ajmi Azathioprine-induced cholestatic hepatitis has been reported in various settings including renal and cardiac transplantation, Wegener granulomatosis, systemic lupus erythematosus, and inflammatory bowel disease. INTRODUCTION. The therapeutic efficacy, bone marrow toxicity, and liver toxicity of azathioprine (AZA) and 6-mercaptopurine (6-MP) may be related to their metabolites: 6-thioguanine (6-TG) and 6-methylmercaptopurine (6-MMP). PubMed Citation (Adding allopurinol to azathioprine therapy led to higher thioguanine and methyl-mercaptopurine levels, thus allowing for reduction in azathioprine dose, and theoretically better efficacy, lower toxicity). In Summary. Commonly reported side effects of azathioprine include: infection, nausea, leukopenia, and vomiting. See below for a comprehensive list of adverse effects. Abstract. Azathioprine hepatotoxicity has been described mainly in renal transplant recipients. Most reported cases are related to lesions of the venous system of the liver: peliosis hepatis, veno-occlusive disease of the liver, perisinusoidal fibrosis, and nodular regenerative hyperplasia of the liver. Azathioprine (AZA), sold under the brand name Imuran among others, is an immunosuppressive medication. It is used in rheumatoid arthritis , granulomatosis with polyangiitis , Crohn's disease , ulcerative colitis , and in kidney transplants to prevent rejection. Azathioprine can cause liver toxicity (for example, in less than 1% of rheumatoid arthritis patients). All patients taking azathioprine require regular testing of blood for blood cell counts and liver tests to monitor for side effects of azathioprine. Other side effects encountered less frequently include Introduction. Azathioprine is a purine analogue and prodrug of mercaptopurine that is used as an immunosuppressive agent in organ transplantation to prevent rejection and in autoimmune diseases as a corticosteroid sparing agent.