A 55-year-old woman with COPD and hypertension developed intensely painful, bright red patches on her face and neck with low-grade fever just 48 hours after her inhaler was switched from formoterol to indacaterol/glycopyrronium.
She reported no new cosmetics, dietary changes, or infections, and blood tests ruled out autoimmune or infectious causes. A skin biopsy confirmed Sweet syndrome, a rare neutrophilic dermatosis driven by abnormal immune responses and usually associated with infections,
malignancies, or medications such as antibiotics, antiepileptics, or vaccines. She was started on oral corticosteroids, leading to rapid improvement within two days, and the inhaler was discontinued.
While Sweet syndrome is rare and often misdiagnosed as lupus, dermatitis, or urticaria, this case is notable because no inhaled medication has previously been documented as a trigger. The report emphasizes the importance for clinicians to remain alert to sudden skin changes following medication adjustments, as even widely used therapies may occasionally provoke unexpected immune-mediated conditions.
Early recognition and treatment can be crucial for patient outcomes.