SPL Set ID: bc6dc4bd-2121-4613-9d90-4a504010c98a

Azathioprine, an immunosuppressive antimetabolite, is available in tablet form for oral administration. Each scored tablet contains 25 mg, 50 mg, 75 mg and 100 mg azathioprine and the inactive ingredients croscarmellose sodium, lactose monohydrate, magnesium stearate, maize starch and povidone K30. Azathioprine is chemically 6-[(1-methyl-4-nitro-1 H -imidazol-5-yl)thio]-1 H -purine. The structural formula of azathioprine is: It is an imidazolyl derivative of 6-mercaptopurine and many of its biological effects are similar to those of the parent compound. Azathioprine is insoluble in water, but may be dissolved with addition of one molar equivalent of alkali. Azathioprine is stable in solution at neutral or acid pH but hydrolysis to mercaptopurine occurs in excess sodium hydroxide (0.1N), especially on warming. Conversion to mercaptopurine also occurs in the presence of sulfhydryl compounds such as cysteine, glutathione, and hydrogen sulfide. FDA approved dissolution test specifications differ from USP. Azathioprine Structure