Clinical and experimental studies have suggested that intraperitoneal noxytiolin prevents adhesion formation. A reliable experimental animal model was therefore established and the effect of noxytiolin on adhesion formation was evaluated in a controlled trial using 80 rats. All 40 rats given Ringer solution developed adhesions, whereas in 7 out of 40 given noxytiolin no adhesions were found (P less than 0-02). Noxytiolin reduced both the total and the mean number of adhesions formed (P less than 0-2) and their mean length of attachment (P less than 0-05). The anti-adhesive effect of noxytiolin may be due to its anticoagulant, cytotoxic or antibacterial properties.