Cytokines are chemical messengers that play a role in the immune system. These cytokines increase the sensitivity of T lymphocytes to rid the body of foreign substances. Tacrolimus suppresses this process by decreasing the production and release of cytokines. When an organ such as a kidney or liver is transplanted from one individual to another, the recipient is treated with immunosuppressants such as tacrolimus. As a result the recipient's immune system is unable to recognize the transplanted organ as foreign and unable to attack and reject the organ.
Atopic dermatitis includes an immune component wherein the skin's immune system is over-reactive.
It seems logical that drugs which calm down the immune system should help treat atopic dermatitis. Currently, topical application of tacrolimus is extensively being studied to treat and relieve symptoms of atopic dermatitis. In adults, the rash can be distributed across the neck, face, upper chest, elbows and knees. In children, the disease occurs on the head, diaper region, and areas of the arms and legs. Scratching makes the condition worse by releasing more and more cytokines and antibodies.