Tofacitinib is primarily used in the treatment of autoimmune and inflammatory conditions. It is effective in managing moderate to severe rheumatoid arthritis, especially in patients who have not responded well to methotrexate or other disease-modifying antirheumatic drugs (DMARDs). It works by suppressing the immune system’s overactivity, reducing joint pain, swelling, and stiffness. It is also approved for treating psoriatic arthritis and ulcerative colitis, helping to induce and maintain remission and improve quality of life. In some cases, it is used off-label for other immune-mediated conditions such as alopecia areata or certain types of vasculitis. Due to its mechanism of action—targeting Janus kinase (JAK) pathways—it offers an oral alternative to biologic injectable therapies, providing convenience for long-term management. However, its use requires monitoring for infections, blood clots, and changes in blood cell counts due to immunosuppressive effects.