What are the most serious side effects of filgotinib?

Filgotinib is a selective Janus kinase 1 (JAK1) inhibitor, primarily used to treat moderately to severely active rheumatoid arthritis (RA) and moderately to severely active ulcerative colitis (UC). The drug reduces the inflammatory response by inhibiting JAK1 signaling, thereby effectively relieving symptoms in patients with rheumatoid arthritis and ulcerative colitis. Although filgotinib has shown significant efficacy in treatment, like all medications, it may cause some side effects. Understanding these side effects is critical to ensuring safe use for patients.

Among the common side effects of filgotinib, the most serious side effects often include infections and immune system-related side effects. Because filgotinib suppresses part of the immune response by inhibiting the JAK1 pathway, patients may be more susceptible to infection. In particular, upper respiratory tract infections (URTI) and urinary tract infections (UTI) are the most common types of infections. These infections may manifest as cough, flu symptoms, frequent urination, urgency, etc. Patients should closely observe these symptoms while taking the medicine and seek medical attention promptly.

In addition to infection, nausea is also one of the common adverse reactions of filgotinib. Although these symptoms are usually mild and occur early in the course of treatment, patients can relieve symptoms by adjusting their diet or taking anti-nausea medications. In addition, lymphopenia) is another common side effect of filgotinib. Lymphocytes are important cells in the immune system. When reduced, lymphocytes may lead to decreased immunity and increase the risk of infection. Dizziness is also an occasional side effect of filgotinib.

Although the above side effects are more common in some patients, most side effects are mild in severity and usually resolve gradually with continued treatment. However, patients should still undergo regular health examinations while taking filgotinib, especially monitoring indicators such as infection, blood routine, and immune function to ensure the safety of drug use.

Keyword tags: filgotinib, side effects, upper respiratory tract infection, nausea, lymphopenia, urinary tract infection

Reference materials:https://en.wikipedia.org/wiki/FilgotinibA