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What is Viagra like medicine is given in which condition: March 2007 and explain in detail?
Ans. A: Pulmonary Hypeension Since NO is an impoant regulator of pulmonary vascular resistance, PDE-5 inhibitors lower pulmonary aerial pressure. Sildenafil is more selective for pulmonary circulation than vardenafil, and is the only PHosphoDiEsteras-5 inhibitor shown to improve aerial oxygenation in pulmonary hypeension. Sildenafil has now become the drug of choice for pulmonary aerial hypeension.