OBJECTIVES: The aim of this systematic review (SR) is to compare efficacy and safety of bosentan, epoprostenol, iloprost, sildenafil and treprostinil with conventional treatment (CT) in patients with pulmonary arterial hypertension (PAH). METHODS: Analysis was performed according to “Polish Guidelines on Health Technology Assessment”, 2007 and “Cochrane Handbook for Systematic Reviews of Interventions”. In order to identify RCTs medical databases were searched: e.g. Medline, EmBase and Cochrane Library. Calculations and metaanalyses were performed using StatsDirect statistical software. RESULTS: Nineteen RCTs (treatment period 2-16 weeks), in which a total number of 1795 patients with PAH participated, were included in the SR. All patients continued CT with anticoagulants, vasodilators, diuretics and/or digitalis glycosides Bosentan, epoprostenol, iloprost and sildenafil significantly increase exercise capacity (according to the NYHA classification) comparing to placebo in the PAH population: bosentan vs. placebo: OR=2.25 (95%CI: 1.21; 4.18); epoprostenol vs. placebo: OR=37.99 (95%CI: 8.43; 171.22); iloprost vs. placebo: OR=2.25 (95%CI: 1.02; 5.13), sildenafil vs. placebo: OR=6.94 (95%CI: 2.78; 17.31). In bosentan, iloprost, sildenafil and treprostinil groups significantly higher improvement in exercise capacity, measured using the 6-minute walk test, was found comparing to placebo: WMD=43.33m (95%CI: 27.55; 59.12) for bosentan vs. placebo; 36.4m (p=0.004) – iloprost vs. placebo; 55.82m (95%CI: 38.03; 73.61) – sildenafil vs. placebo and 16.00m (95%CI: 4.40; 27.60) - treprostinil vs. placebo. In safety analysis no statistically significant differences were observed between bosentan and placebo as well as sildenafil and placebo groups. Comparing to placebo, in epoprostenol group significantly more often jaw pain, nausea and diarrhea occurred, in iloprost group there was higher incidence of serious syncope or flushing and jaw pain and in the treprostinil group –sudden vasodilation, edema, jaw pain and reaction, pain, hematoma or induration at the injection site. CONCLUSIONS: The use of these five drugs in addition to CT is more effective than CT alone.