Xeljanz is prescribed to the patient having severe rheumatoid arthritis. Xeljanz 5 mg is the recommended dose and is taken with or without food once a day. The most common side effects of this medication are respiratory tract infections, headaches, and diarrhea. Before starting the medication, always tell your doctor your medical history like any liver disease, kidney, TB, or hepatitis C. If you experience any allergies then immediately contact your doctor.xeljanz 5 mg price in India depends according to different pharmacies and wholesalers. It cost around ₹1105.73/Tablet.