Studies at the Cleveland Clinic have suggested that 6-TG levels greater than 260 are kopen imuran c o d necessary for clinical benefit and 6-MMP levels over 5700 have been associated with liver toxicity. Blood levels are of little predictive value for therapy since the magnitude and duration of clinical effects correlate with thiopurine nucleotide levels in tissues rather than with plasma drug levels. Azathioprine is immunosuppressive, delayed hypersensitivity and cellular cytotoxicity tests being suppressed to greater degree than are antibody responses. Use with Aminosalicylates: There is in vitro evidence that aminosalicylate derivatives. Tell your doctor immediately if you develop any of the following: unusual skin changes, change in the appearance size of moles, unusual growths lumps, swollen glands, unexplained weight loss, night sweats, unexplained itching, signs of infection. This agent has little effect on established graft rejections or secondary responses. It does not take the place of talking to your doctor or pharmacist.