In order to verify the adhesion preventing capability of peat and peat components, 180 female rats were subjected to therapeutic bathing after standardised lesions had been placed on both uterine horns and the peritoneum of the anterior abdominal wall. From the 3rd and 7th day after surgery, respectively, randomized groups of animals consisting of 20 animals each were bathed in tap water, pure fresh peat, peat solution after pressing, centrifugation and filtration, and a solution of humic acids extracted from peat, all at the same temperature. One week after bathing for three weeks, the rats were relaparotomized, and quality and degree of the adhesions found were documented. Significant less and minor (p less than 0.001) adhesions were found in animals bathed in humic acid solution compared to the animals which had not been bathed at all. Peat solution and fresh peat reduced the formation of adhesions significantly, too, while warm water baths did not show any antiadhesive effect. Our results suggest humic acids to be the most effective component of peat with regard to the prevention of adhesions.