The aim of this study was to evaluate the efficacy of intranasal salmon calcitonin compared to a nonsteroidal anti-inflammatory drug (NSAID) in patients with Sudeck's atrophy by means of quantitative three-phase bone scanning. Included in the study were 14 patients with Sudeck's atrophy whose diagnoses were confirmed by clinical and radiological examinations. Seven patients were treated with intranasal salmon calcitonin (100 IU twice daily) and 1 g elementary calcium daily for 5 weeks. The other group of seven patients was treated with 75 mg indomethacin daily for 5 weeks. The effectiveness of both treatments was analysed by comparing quantitative three-phase bone scans which were performed before and after the treatment. Bone-to-soft tissue ratios were calculated from static (delayed) images and scintigraphic evaluations were done both visually and quantitatively. Patients who received the calcitonin/calcium regimen showed reduced bone/soft tissue indices after therapy whereas patients who received indomethacin showed no change or showed increased indices. In conclusion, the results show that intranasal salmon calcitonin and calcium treatment is more effective than NSAIDs in patients with Sudeck's atrophy.