Tacrolimus

n. (Medicine) drug which helps to reduce and prevents the rejection of transplant of body organs and bone marrow transplants

Tacrolimus (also FK-506 or Fujimycin) is an immunosuppressive drug whose main use is after allogenic organ transplant to reduce the activity of the patient's immune system and so the risk of organ rejection. It is also used in a topical preparation in the treatment of severe atopic dermatitis ("eczema"), severe refractory uveitis after bone marrow transplants, and the skin condition vitiligo. It is a 23-membered macrolide lactone discovered in 1984 from the fermentation broth of a Japanese soil sample that contained the bacteria Streptomyces tsukubaensis.
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Tacrolimus /tac·ro·li·mus/ a macrolide immunosuppressant having actions similar to those of cyclosporine ; used to prevent rejection of organ [more]Tacrolimus - Community and Resources

A drug used to help reduce the risk of rejection by the body of organ and bone marrow transplants.