Tacrol is a brand of Tacrolimus. Tacrol is available in 0.5 mg, 1 mg, 5 mg capsules.
Tacrolimus is also a drug that prevents certain cells from causing rejection. Tacrolimus is used to prevent or treat rejection after kidney transplant. It prevents rejection by inhibiting the cells in the immune system that cause rejection. Tacrolimus may be used by itself or in combination with other anti-rejection medications to prevent rejection.