A number of drugs may result in hypersensitivity pneumonitis, including methotrexate, cyclophosphamide and antidepressants such as fluoxetine and amitriptyline (Ellis et al, 2000) . The radiological and HRCT findings are identical to those seen in hypersensitivity pneumonitis secondary to the inhalation of organic dust and consist of bilateral ground-glass opacities and/ or small poorly defined centrilobular nodular opacities (Ellis et al, 2000; Cleverley et al, 2002) . The majority of patients also demonstrate lobular areas of air trapping, although this is less Figure 1 High-resolution CT images demonstrating radiology of drug-associated ILD. (A) A 77-year-old man with diffuse alveolar damage secondary to amidarone; note the extensive bilateral ground-glass opacities, airspace consolidation and bilateral pleural effusions. (B) A 36-year-old woman with hypersensitivity pneumonitis secondary to sertraline; note the extensive bilateral ground-glass opacities and lobular areas of air trapping (arrows). (C) A 69-year-old man with BOOP-like reaction to amiodarone; note the mild reticulation and bilateral areas of consolidation and ground-glass opacities in a predominantly peribronchial distribution. (D) A 47-year-old man with NSIP reaction to bleomycin; note the extensive bilateral ground-glass opacities with mild superimposed reticulation. (E) A 47-year-old man with eosinophilic pneumonia reaction to dilantin; note the patchy bilateral areas of consolidation involving the peripheral regions of the upper lobes. apparent than in extrinsic allergic alveolitis to airborne agents (Ellis et al, 2000) ( Figure 1B ).