A JAK inhibitor tablet
Upadacitinib
An oral JAK inhibitor that calms an overactive immune system in rheumatoid arthritis and other inflammatory conditions.
What is Upadacitinib?
Upadacitinib is a once-daily tablet from the JAK inhibitor group, used for rheumatoid arthritis and several other inflammatory conditions such as some types of arthritis, eczema and bowel inflammation when other treatments have not done enough. It blocks chemical signals inside immune cells that drive inflammation, easing symptoms like joint pain, swelling and stiffness. As it lowers part of the immune response, the main concern is a higher risk of infections, including shingles, alongside cautions about blood clots and heart problems, especially in older people who smoke. You are screened for infections such as tuberculosis and hepatitis before starting and have regular blood tests during treatment. Report any fever, new rash or signs of infection without delay.
Education and reference only. This is a plain-language guide to Upadacitinib — it deliberately contains no doses. Doses depend on the person, the brand and the reason for treatment, and belong with your prescriber. Always check the BNF, the product labelling (SmPC) and follow medical advice.
What it is
Upadacitinib is a modern targeted medicine for inflammatory disease, taken once a day as a slow-release tablet. It is a JAK inhibitor, working inside immune cells rather than on their surface. In the UK it is used for moderate to severe rheumatoid arthritis and a range of other inflammatory conditions, including some forms of arthritis, severe eczema and inflammatory bowel disease, usually when earlier treatments have not controlled the condition well enough.
How it works
Inflammatory conditions are driven by messenger chemicals that activate immune cells through enzymes called Janus kinases. Upadacitinib blocks these enzymes so the inflammatory signalling is reduced, which can calm joint pain, swelling, skin inflammation or bowel symptoms depending on the condition. Because these pathways also help fight infection, turning them down increases the chance of infections, which underlies its key cautions.
Company & origin
Originated / developed by: AbbVie.
An oral JAK inhibitor used in the UK for rheumatoid arthritis and several other inflammatory conditions when other treatments have not worked well enough.
What it treats
Conditions Upadacitinib is used for
Practical use
How to take Upadacitinib
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Take the slow-release tablet once a day, swallowed whole without crushing or splitting, with or without food.
- Complete the screening tests, such as for tuberculosis and hepatitis, before you start.
- Attend your blood test appointments, which check your blood counts, liver and cholesterol.
- Tell your team promptly about any fever, cough, sore throat, new rash or a painful blistering rash that could be shingles.
- Seek urgent help for leg swelling or pain, or sudden breathlessness or chest pain, which can be signs of a clot.
- Avoid live vaccines and check with your team before any vaccination or planned operation.
Weighing it up
Advantages & disadvantages of Upadacitinib
Advantages
- Taken as a single daily tablet, avoiding the injections used for some other advanced treatments.
- Works across several inflammatory conditions, from arthritis to severe eczema and bowel inflammation.
- Can act quickly to reduce symptoms when standard treatments have not been enough.
Disadvantages
- Increases the risk of infections, including shingles, because it lowers part of the immune response.
- Carries cautions about blood clots and heart problems, especially in older smokers and those with risk factors.
- Requires screening before starting and ongoing blood tests, and is not suitable in pregnancy.
Practical use
Good to know
As with other JAK inhibitors, the leading safety concern is infection: it can make ordinary infections more frequent or serious, and shingles is notably more common, so fevers, coughs, sore throats or a new rash should be reported. There are also cautions about blood clots in the legs and lungs and about heart problems, so it is used carefully in older people, smokers and those with heart or clotting risk. Before starting you are screened for hidden infections such as tuberculosis and hepatitis, and you have blood tests for blood counts, liver and cholesterol before and during treatment. Live vaccines are generally avoided, and being up to date with recommended vaccinations beforehand is helpful. It is not used in pregnancy and reliable contraception is advised.
Who should not take it / use with caution
- People with a serious active infection, including active tuberculosis, should not start it until treated.
- It is avoided in pregnancy and breastfeeding, and reliable contraception is advised during treatment.
- Used with great caution or avoided in those at higher risk of blood clots or heart disease, such as older smokers.
Monitoring
- Screening for tuberculosis, hepatitis and other infections before starting.
- Regular blood tests for blood counts, liver function and cholesterol during treatment.
- Watching for signs of infection, shingles, blood clots and heart symptoms throughout.
Side effects
- Infections such as colds, chest and urinary infections, and an increased risk of shingles.
- Headache, acne, raised cholesterol and changes in blood counts and liver tests on monitoring.
- Rarely, blood clots in the legs or lungs, or more serious heart or infection problems.
Key interactions
- Combining it with other strong immune-suppressing medicines further raises the infection risk.
- Some antifungal and other medicines change its levels in the body, so caution is needed.
- Live vaccines should be avoided, and other medicines affecting the immune system need careful review.
Available as: Slow-release tablets taken by mouth.
Answers
Upadacitinib: frequently asked questions
What conditions is upadacitinib used for?
It is used for rheumatoid arthritis and several other inflammatory conditions, including some types of arthritis, severe eczema and inflammatory bowel disease, usually when other treatments have not worked well enough.
Why can it cause more infections?
It lowers part of the immune response that fights infection, so colds, chest and urinary infections, and shingles in particular, can be more likely; report signs of infection promptly.
Can I crush or split the tablet?
No, it is a slow-release tablet and should be swallowed whole, as crushing or splitting it can release the medicine too quickly.
Do I need blood tests while taking it?
Yes, you have regular blood tests to check your blood counts, liver and cholesterol, along with infection screening before you start.
Is it safe in pregnancy?
No, it is not used in pregnancy, and reliable contraception is advised during treatment; talk to your team about any plans.
The wider class
About JAK inhibitors
Upadacitinib belongs to the jak inhibitors class. For how the class as a whole works, its shared safety principles and monitoring, see the full guide.
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Authoritative sources
- BNF
- NICE CKS
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