Xeljanz can help when standard treatments fail — but it isn’t a pill to take lightly. This short guide explains what Xeljanz treats, how it works, the biggest safety concerns, and clear steps you can take to use it more safely.
Xeljanz is the brand name for tofacitinib, an oral medicine that blocks enzymes called Janus kinases (JAKs). Blocking JAKs reduces immune system activity, which eases inflammation. Doctors commonly use Xeljanz for rheumatoid arthritis, psoriatic arthritis, and ulcerative colitis when other drugs haven’t worked. It can work faster than some biologics because you take a pill rather than injections.
Typical dosing varies by condition. For rheumatoid arthritis, many people take 5 mg twice daily or 11 mg once daily (extended-release). For ulcerative colitis, higher induction doses may be used short-term, then lowered for maintenance. Your doctor will tell you the exact plan based on your diagnosis and other medications.
Xeljanz can cause serious side effects. The most important risks are infections (including TB), blood clots, and changes in blood counts and cholesterol. The FDA has added warnings about an increased risk of serious heart events and certain cancers in some patients, especially older people with heart disease or long smoking histories.
Before starting Xeljanz, expect these tests: TB screening, hepatitis B/C checks, baseline CBC (blood count), liver tests, and fasting lipids. Your doctor will repeat blood tests regularly—often at 4–8 weeks after starting and then every few months. If you develop fever, persistent cough, unexplained bruising, severe shortness of breath, or calf pain, contact your provider right away.
A few practical things to remember: avoid live vaccines while on Xeljanz; tell your doctor about recent vaccinations. Mention all medicines you take — strong CYP3A4 inhibitors (like ketoconazole) can raise Xeljanz levels, and strong inducers (like rifampin) can lower them. If you’re pregnant, planning pregnancy, or breastfeeding, talk to your provider — data are limited and choices depend on your situation.
Missing a dose: if you take twice daily, take the missed dose as soon as you remember unless it’s close to the next dose; don’t double up. If cost or insurance is a problem, ask your clinic about patient assistance programs or prior authorization help—many practices assist with this.
Final practical tip: keep a simple checklist—baseline labs, TB and hepatitis tests, no live vaccines, watch for infection signs, and regular follow-up. That checklist makes Xeljanz safer and helps you and your doctor spot problems early.
Apr, 20 2025