Leflunomide is a potent immunomodulatory agent primarily used in the management of autoimmune conditions such as rheumatoid arthritis. It functions by inhibiting the dihydroorotate dehydrogenase enzyme, which plays a crucial role in the de novo synthesis of pyrimidine, thereby reducing the proliferation of activated lymphocytes. This mechanism helps in controlling the inflammatory processes associated with autoimmune diseases, making Leflunomide an effective option for patients who require long-term management of their symptoms.

In addition to its primary use, Leflunomide is sometimes considered in off-label applications for other autoimmune disorders, reflecting its versatility in modulating immune responses. The pharmacokinetics of Leflunomide involve its conversion to an active metabolite, teriflunomide, which is responsible for its therapeutic effects. This conversion allows for a sustained action, contributing to its efficacy in chronic conditions. Prescribers should be aware of its potential side effects, including hepatotoxicity and teratogenicity, necessitating regular monitoring of liver function tests and ensuring effective contraception in women of childbearing potential.

Given its immunosuppressive properties, Leflunomide may increase the risk of infections, and patients should be monitored for signs of infection during treatment. Drug interactions are also a consideration, as Leflunomide can interact with other medications metabolized by the liver, potentially altering their efficacy or increasing toxicity. Understanding these aspects of Leflunomide is essential for optimizing patient outcomes and minimizing adverse effects, making it a valuable component in the therapeutic arsenal for autoimmune diseases.