In a series of articles the authors discuss literature data concerning epidemiology of pulmonary arterial hypertension (PAH), its modern classification, peculiarities of its pathogenesis and treatment in various diseases and conditions. The last 14-th communication contains consideration of issues of differentiated administration of modern pulmonary vasodilators to patients with PAH taking into account etiology and severity of the disease, availability of evidence based efficacy and safety data, method of application, and contraindications. In patients with PAH of II and III functional class (FC) endothelin receptor blocker bosentan is believed to be the drug of first choice. Bosentan can be administered orally. In patients with significant liver involvement phosphodiesterase inhibitor type 5 sildenafil should be used instead of bosentan for long term treatment of PAH. Sildenafil also can be taken orally. If bosentan is not sufficiently effective it can be combined with sildenafil; inhalations of prostanoid iloprost can be added to this combination when necessary. Is this tiple combination is not effective iloprost inhalations can be replaced by subcutaneous treprostinil or continuous intravenous infusion of epoprostenol. In patients with IV FC PAH therapy is started with subcutaneous administration of treprostinil or infusion of epoprostenol, while bosentan or/and sildenafil is added when necessary.