OBJECTIVES: Our aim was to perform a pilot study to investigate whether iontophoresis of acetic acid, followed by ultrasound, might be a safe and effective treatment for systemic sclerosis (SSc)-related calcinosis. This combination treatment has been used in other calcifying disorders. METHODS: Three female patients (ages 51, 62 and 59 yr) were studied. Each underwent treatment nine times over a 3-week period. Iontophoresis was with 2-5% acetic acid at 100 microA for 20 min, followed by ultrasound at 1.5 W/cm(2) for 8 min at each visit. The primary endpoint was the degree of radiographic calcinosis as quantified by image analysis after adjusting for soft tissue change. RESULTS: There were no side-effects from treatment. Mean radiographic intensity fell in all patients (by 18.0, 8.9 and 8.5%), although the maximum density and the area of calcinosis fell in only one patient. However, none of the patients reported any benefits from the treatment. CONCLUSIONS: In this small pilot study none of the patients experienced clinical improvement, despite an intensive treatment schedule over 3 weeks. However, there may have been some radiographic improvement. Given that there is currently no effective treatment for SSc-related calcinosis a larger study incorporating higher 'doses' of iontophoresis is indicated.