Upadacitinib‐Related Osteonecrosis of the Jaw

ABSTRACT Background Upadacitinib is a Janus kinase ( JAK ) inhibitor, part of a class of medications that modulate immune system signalling. These drugs are commonly used to manage inflammatory conditions such as rheumatoid arthritis and ulcerative colitis by reducing inflammation and pain. Methods To our knowledge, we report the first documented case of spontaneous osteonecrosis of the jaw associated with upadacitinib. Results In this report, we explore the drug's mechanism of action and its potential role in the pathogenesis of medication‐related osteonecrosis of the jaw (MRONJ). Conclusion Though rare, upadacitinib should be added to the growing list of drugs implicated in MRONJ.