Portopulmonary hypertension (POPH) is regarded as a subtype of pulmonary arterial hypertension (PAH); however, established PAH therapies have not been evaluated for this condition. The current authors treated 14 patients (four male, 10 female; mean (range) age 55 (39-75) yrs) with moderate (n = 1) or severe (n = 13) POPH caused by alcoholic liver disease (n = 7), chronic viral hepatitis (n = 3), autoimmune hepatitis (n = 3), and hepatic manifestation of hereditary haemorrhagic teleangiectasia (n = 1) with oral sildenafil. Eight patients were newly started on pulmonary vasoactive treatment, while six patients were already on treatment with inhaled prostanoids (iloprost, n = 5; treprostinil, n = 1). During treatment with sildenafil, mean +/- sd 6-min walk distance increased from 312 +/- 111 m to 397 +/- 99 m after 3 months, and 407 +/- 97 m after 12 months. Mean +/- sd pro-brain natriuretic peptide levels decreased from 582 +/- 315 ng x mL(-1) to 230 +/- 278 ng x mL(-1), and to 189 +/- 274 ng x mL(-1) after 3 and 12 months, respectively. Two patients died after 1 and 2 months from liver failure and cardiac failure, respectively. There was a similar response to sildenafil treatment after 3 and 12 months in patients on monotherapy and those on combination therapy. In conclusion, sildenafil might be effective in monotherapy and in combination therapy with inhaled prostanoids in portopulmonary hypertension, leading to significant improvement by 3 months and sustained response over 12 months.