Bisphosphonates are synthetic compounds that are taken up preferentially by skeletal tissue and suppress osteoclast mediated bone resorption. They are being used increasingly in the treatment of osteoporosis.¹ Bronchoconstriction caused by bisphosphonates has been described² but drug induced pneumonitis has not previously been reported.³ This is the first report of interstitial pneumonia induced by the bisphosphonate risedronate.

A woman developed an intramuscular mass in her right arm at the age of 51 years. Sarcoidosis was diagnosed by non-necrotising epithelioid granulomas in the resected specimen of the mass, bilateral hilar lymphadenopathy on the chest radiograph, a negative reaction to tuberculin test, and an increase in the serum angiotensin converting enzyme (ACE) level to 27.9 U/ml. She had pain in her right …