Leflunomide

Leflunomide is a medication primarily used to treat rheumatoid arthritis and psoriatic arthritis, conditions characterized by chronic inflammation and joint damage. As an immunomodulatory agent, leflunomide helps regulate the immune system to reduce inflammation and slow disease progression. It belongs to the disease-modifying antirheumatic drug (DMARD) class, which includes a variety of drugs that differ in their chemical makeup and how they work in the body.

At the molecular level, leflunomide functions by inhibiting pyrimidine synthesis, crucial for DNA and RNA production, thus affecting the proliferation of rapidly dividing cells, including those in the immune system. This mechanism helps in controlling the overactive immune response in arthritis.

While effective, leflunomide can have side effects, notably impacting the liver. Patients may experience elevations in liver enzymes, indicating liver stress or damage, and in rare cases, it can lead to severe liver injury. Therefore, monitoring liver function is crucial during treatment with leflunomide.

Additionally, leflunomide has various roles and activities in the body. It acts as a non-steroidal anti-inflammatory drug (NSAID) and has properties of an antineoplastic (anti-cancer), antiparasitic, and immunosuppressive agent. It also inhibits certain enzymes, contributing to its diverse therapeutic and side effect profile.