A 61-year-old woman was admitted to our hospital because of intractable pneumonia refractory antibiotic treatment. Chest computed tomography showed bilateral consolidations and ground-glass opacities, but they gradually decreased without any intervention. On a follow-up examination after discharge, abnormal lung shadows were reconfirmed 10 days later. An interview revealed that she had been taking a dietary supplement with glucosamine and had switched to a different formulation approximately 1 month prior to presentation. Oral administration of the supplement was discontinued during the hospitalization, but restarted thereafter. The new supplement contained not only glucosamine, but also herbal medicines as additional components that were not included in the previous supplement formulation. We diagnosed with drug-induced pneumonitis caused by herbal medicines. This valuable case underscores the importance of considering additional components in the suspected drugs and dietary supplements taken by patients with drug-induced pneumonitis.