OBJECTIVE: In order to provide an overview of current knowledge, the literature was systematically examined for clinical studies, which evaluate the safety and effectiveness of bosentan in pediatric pulmonary arterial hypertension (PAH). SOURCES: 3 databases (MEDLINE, EMBASE and BIOSIS) were searched for the period January 2000 - October 2007 using the key words 'pulmonary arterial hypertension', 'bosentan', and 'pediatric patients/children'. RESULTS: Of 165 identified publications, 21 clinical studies were selected: 1 interventional prospective, 6 observational prospective, 5 observational retrospective, and 9 case reports/case series. In the absence of controlled trials, these 21 studies represent the current evidence on the effectiveness and safety of bosentan in the treatment of pediatric PAH. Bosentan appears to improve long-term functional status and hemodynamics in children with PAH but improvement in exercise capacity is not consistently demonstrated. Promising results are reported for the combination of bosentan with other PAH-specific treatments although guidelines for instituting combination therapy have not been defined. Overall, no safety concern is raised by these studies; adverse events, including liver enzyme elevations, appear to be less frequent than reported in the adult PAH clinical trials. CONCLUSION: Recent experience, although uncontrolled, suggests that bosentan is a well-tolerated and effective therapy for pediatric PAH.