Patients with Eisenmenger syndrome generally die prematurely from complications directly due to their pulmonary hypertension and cyanosis, or due to intercurrent events that are poorly tolerated because of the underlying inadequate cardiopulmonary reserve. To date, clinical management has aimed at avoiding situations that would destabilise their condition and treatment of its complications. However, therapeutic prospects are starting to look more encouraging. Results from a small study with the oral dual endothelin receptor antagonist, bosentan, have shown improved exercise capacity. Additionally, there appears to be a possible role for the phosphodiesterase-5-inhibitor, sildenafil, in the treatment of Eisenmenger pulmonary hypertension.