2026 Volume 52 Issue 8 Pages 554-559
A 75-year-old woman presented to an orthopedic clinic at another hospital for periarthritis of the shoulder and was prescribed nijutsuto. On day 24 after initiation, she developed exertional dyspnea. On Day 26, she discontinued nijutsuto on her own because she perceived no improvement in her shoulder symptoms.
On day 37, she again experienced exertional dyspnea, with oxygen desaturation below 90％ on pulse oximetry, prompting a visit to an internal medicine clinic at another hospital. Chest computed tomography suggested interstitial pneumonia, and she was referred to our institution. Upon admission, intravenous prednisolone was initiated under a provisional diagnosis of idiopathic interstitial pneumonia.
Her medication history was reviewed using her medication notebook and the brought-in drugs. On hospital Day 3, a ward pharmacist identified through the online eligibility verification system that she had been taking nijutsuto. Drug-induced interstitial pneumonia caused by nijutsuto was suspected and reported to the attending physician.
Her symptoms subsequently improved, and prednisolone was gradually tapered. After completion of prednisolone therapy, a drug-induced lymphocyte stimulation test was performed and yielded negative results. Based on the clinical course and bronchoalveolar lavage findings, she was finally diagnosed with acute drug-induced eosinophilic pneumonia caused by nijutsuto.
The online eligibility verification system enabled more comprehensive medication history retrieval than conventional methods, which contributes to accurate diagnosis and appropriate pharmacotherapy.
