XELJANZ may cause serious side effects, including Hepatitis B or C activation infection in people who carry the virus in their blood. If you are a carrier of the Hepatitis B or C virus (viruses that affect the liver), the virus may become active while you use XELJANZ. Your healthcare provider may do blood tests before you start treatment with XELJANZ and while you are using XELJANZ. Tell your healthcare provider if you have any of the following symptoms of a possible Hepatitis B or C infection: feel very tired, little or no appetite, clay-colored bowel movements, chills, muscle aches, skin rash, skin or eyes look yellow, vomiting, fevers, stomach discomfort, or dark urine.
Common side effects of XELJANZ in ulcerative colitis patients include nasal congestion, sore throat, and runny nose (nasopharyngitis), increased cholesterol levels, headache, upper respiratory tract infections (common cold, sinus infections), increased muscle enzyme levels, rash, diarrhea, and shingles (herpes zoster).
These are not all of the possible side effects of
Patients should always ask their doctors for medical advice about adverse events. You are encouraged to report adverse events related to Pfizer products by calling