Objective: We investigated the effect of carnitine on wound heating of trachea in tracheotomyzed rats. This study was undertaken to test the hypothesis that treatment with carnitine would protect the wound tissue, which was evaluated by measuring nitrite and nitrate, thus nitric oxide, malondialdehyde and cholinesterase in blood, and examining the histopathological changes. Methods: Standard vertical tracheotomy was performed on 24 Wistar-Albino type rats. Then the animals were randomly divided into two groups; group A (the study group) was administered intraperitoneal carnitine 100 mg/kg for 10 days; group B (the control group) was administered intraperitoneal saline for 10 days. On the 10th day, all animals were decanulated. Three weeks later, cardiac blood samples were taken for biochemical assays and trachea specimens were harvested for histopathologic examination. Results: In the carnitine-administered group, granulation tissue thickness resulting from the wound heating in the level of tracheotomy incision was lower compared to the control group (P<0.01). When serum malondialdehyde levels were considered, a lower malondialdehyde level. was found in the carnitine-administered group (P<0.01). However, serum nitric oxide levels were close to each other in both groups (P>0.05), while serum cholinesterase level was higher in the carnitine-administered group than in the control group (P<0.01). Conclusion: Carnitine treatment partially prevents and significantly reduces the severity of tracheotomy induced laryngotracheal stenosis. (C) 2003 Elsevier Science Ireland Ltd. All rights reserved.