Imusporin 100 Capsule is an immunosuppressant. It works by suppressing your body’s immune response to help accept a newly transplanted organ (e.g., liver, kidney or heart). In rheumatoid arthritis, this immunosuppressive effect reduces inflammation (swelling) of joints and limits joint damage. In psoriasis, it works by reducing the activity of certain immune cells that cause overproduction of skin cells, thus improving scaling and redness.