Janus kinase inhibitors (JAK inhibitors) are a class of small molecules that block the activity of Janus kinases, which are enzymes involved in the signaling pathways of various cytokines and growth factors that mediate immune and inflammatory responses. JAK inhibitors have been developed for the treatment of several inflammatory conditions, including rheumatoid arthritis, psoriasis, and inflammatory bowel disease.

JAK inhibitors can selectively target specific JAK enzymes, such as JAK1, JAK2, JAK3, and TYK2, leading to modulation of the immune response and reduction of inflammation. The use of JAK inhibitors in dermatology is increasing, with several JAK inhibitors approved for the treatment of moderate-to-severe atopic dermatitis, including tofacitinib, baricitinib, and upadacitinib.

JAK inhibitors have also shown promise in the treatment of other inflammatory skin conditions, such as alopecia areata, vitiligo, and chronic spontaneous urticaria. However, JAK inhibitors can have potential side effects, including increased risk of infections, anemia, and liver toxicity. Therefore, careful monitoring of patients receiving JAK inhibitors is recommended.

In this learning module, you will find a comprehensive review of the different JAK inhibitors used in dermatology, their mechanisms of action, indications, contraindications, adverse effects, and drug interactions.

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