What is tofasitinib?

Tofacitinib is a medication used to treat certain autoimmune diseases, such as rheumatoid arthritis, psoriatic arthritis, and ulcerative colitis. It works by blocking Janus kinases (JAKs) enzymes, which play a key role in the immune system's response to inflammation, thereby reducing swelling and pain in the affected areas. Tofacitinib is available as an oral tablet and is usually taken twice daily with food. Some common side effects include infections, diarrhea, headaches, and changes in blood pressure. In rare cases, it can cause serious infections or blood clots, so close monitoring by a doctor is recommended during treatment.