baricitinib at a glance
Medicine class
Selective, reversible JAK1 and JAK2 inhibitor
Licensed uses
Rheumatoid arthritis, atopic dermatitis, severe alopecia areata and specified forms of juvenile idiopathic arthritis
Administration
Oral tablets that may be taken with or without food
Treatment oversight
Started by a clinician experienced in treating the relevant condition
What is baricitinib used for?
Licensed uses represented by the selected products are:
Moderate to severe active rheumatoid arthritis in adults after inadequate response or intolerance to disease-modifying treatment; it may be used alone or with methotrexate.
Moderate to severe atopic dermatitis in adults and children aged 2 years and over who are candidates for systemic treatment.
Severe alopecia areata in adults.
Active polyarticular, enthesitis-related or juvenile psoriatic arthritis in children aged 2 years and over after inadequate response or intolerance to prior disease-modifying treatment.
NHS England also commissions specialist, non-licensed use for defined monogenic interferonopathies in adults and children aged 2 years and over.
How does baricitinib work?
Baricitinib reversibly inhibits JAK1 and JAK2, enzymes that pass signals from cytokine receptors into cells. This reduces STAT protein activation and dampens immune and inflammatory pathways.
How to take baricitinib
Swallow the prescribed tablet with water, with or without food. For children unable to swallow tablets, the product information permits dispersion in room-temperature water. Give the whole mixture and a water rinse of the container. Use only water and follow the supplied leaflet or clinical team's instructions.
Do not stop treatment without discussing it with the prescribing team.
Tell healthcare professionals that baricitinib is being taken, particularly before vaccination, surgery or treatment for infection.
baricitinib side effects
Common or expected effects
- Upper respiratory infections such as colds
- Raised cholesterol on blood testing
- Headache
- Cold sores or shingles
- Urinary infection or gastroenteritis
- Nausea or abdominal discomfort
- Acne or rash
- Changes in liver enzymes, platelet count or creatine kinase on blood testing
Get urgent medical advice
- Serious infection, including pneumonia or severe shingles
- Blood clot in a limb or lung
- Heart attack or stroke symptoms
- Severe allergic reaction
- Diverticulitis or gastrointestinal perforation
- Important blood-cell or liver abnormalities
baricitinib in pregnancy
Baricitinib is contraindicated during pregnancy, and effective contraception is advised during treatment and afterwards. Anyone planning pregnancy or becoming pregnant while taking it should contact their specialist promptly; available human pregnancy evidence for JAK inhibitors remains limited.
baricitinib while breastfeeding
Baricitinib should not be used while breastfeeding because transfer into human milk is unknown and risk to the infant cannot be excluded. The prescriber should help decide between breastfeeding and treatment.
baricitinib interactions
Check all prescribed, over-the-counter and complementary products with the clinical team. Important examples include:
Probenecid
Strong OAT3 inhibition can substantially increase baricitinib exposure, requiring prescriber review.
Biological DMARDs, biological immunomodulators or other JAK inhibitors
Combination is not recommended because additive immunosuppression and infection risk cannot be excluded.
Azathioprine, tacrolimus or ciclosporin
These potent immunosuppressants may add to immune suppression; evidence for combinations is limited or absent.
Common questions about baricitinib
Answers are fully visible for fast scanning and source review.
Is baricitinib a steroid or a biologic?
No. It is an oral targeted synthetic immunosuppressant that inhibits JAK1 and JAK2.
Can baricitinib be taken with food?
Yes. Food does not have a clinically important effect on exposure, so tablets may be taken with or without food.
Can baricitinib tablets be dispersed in water?
The product information allows water dispersion for children who cannot swallow tablets. Only water should be used, and the complete mixture and container rinse should be given.
Why are blood tests needed?
Baricitinib can alter blood-cell counts, cholesterol, liver enzymes and creatinine, while kidney function affects its clearance.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.