BACKGROUND: Leukotriene antagonists zafirlukast and montelukast have been used by plastic surgeons off-label to prevent and treat capsular contracture in breast implant surgery. At the present, only few studies investigated their efficacy. METHODS: A retrospective analysis was performed to investigate the effectiveness of montelukast in preventing and treating capsular contracture. This study included 177 consecutive women who underwent cosmetic breast surgery using textured silicone prostheses. Same surgeon operated all women using infra-mammary approach and dual-plane pocket and a treatment of at least 3 months of montelukast was offered to them at the regimen of 20mg once a day. Therefore, patients were divided into two groups on the basis of montelukast treatment. Follow-up on montelukast efficacy was obtained by a combination of office chart review and strandardized telephone questionnaire with a minimum follow-up of 4 years. RESULTS: Sixty-seven patients received montelukast for 3–6 months. Mean age of the patients was 35.82 ± 8.71 years (range 19–56 years), and co-morbidity was present in 11.76% of cases. All groups combined had a mean follow-up evaluation of 58.71 ± 13.45 months (range 48–136 months) and mean breast size (cc) of 333.89 ± 107.60 cc (range 155–690 cc). No significant differences were found for the use of montelukast versus control in the prevention of capsular contracture after surgery, although the number of affected patients and the severity of capsular contracture were higher among the patients who did not use montelukast. No adverse effects were found. CONCLUSIONS: Montelukast may prevent and improve symptoms of capsular contracture. However, further studies are needed for justifying its somministration.