Severe acute respiratory distress syndrome caused by Otsujito

BACKGROUND: Kampo prescriptions can cause drug‐induced lung injury (DLI) and acute respiratory distress syndrome (ARDS). However, severe respiratory failure induced by Otsujito (OJT) is extremely rare. High‐dose steroid pulse therapy is generally given to patients with severe DLI. CASE PRESENTATION: A 63‐year‐old man with respiratory distress was admitted to our hospital. The patient was diagnosed with severe ARDS caused by OJT, which had been prescribed 4 weeks prior to admission. Thus, OJT was discontinued, and intensive care for ARDS, including ventilation and prone positioning, was implemented. His respiratory condition rapidly improved after treatment with an initial methylprednisolone dose (1.5 mg/kg/day). He was extubated on day 4 and discharged on day 16. The steroid dose was gradually reduced and discontinued by day 116. CONCLUSION: A severe case of ARDS caused by OJT was successfully treated with low‐dose steroids and specialized intensive care.