In a prospective clinical study we investigated how effective cutaneous Vaseline application was in pain reduction during ESWL. In 150 patients (group 1) Vaseline was applied on a skin area corresponding to the entry site of shockwaves directly before lithotripsy; in 75 patients (group 2) ESWL was performed without Vaseline. Analgesic sedation was needed by 10/150 (6.7%) in group 1 and 27/75 (36.4%) in group 2 (P < 0.001). The median pain score in group 1 was 2.5 +/- 1.05 and that in group 2 was 4.25 +/- 1.13 (P < 0.05). Local Vaseline application significantly reduces pain during ESWL independent of stone location. Most pain results from cavitation at the skin surface and is blocked by Vaseline. Cutaneous Vaseline application to reduce the need for analgesic sedation might be especially useful in outpatient ESWL procedures.