Vidalista 10, containing 10 mg of tadalafil, is primarily used to treat erectile dysfunction, but it can also be prescribed for pulmonary arterial hypertension (PAH). Vidalista 10 mg works by inhibiting the enzyme phosphodiesterase type 5 (PDE5), which is found in the smooth muscle of the pulmonary blood vessels. Inhibition of PDE5 leads to increased levels of cyclic guanosine monophosphate (cGMP), resulting in relaxation and dilation of pulmonary arteries. This reduces pulmonary blood pressure and improves the heart's ability to pump blood efficiently. By decreasing vascular resistance in the lungs, Vidalista 10 helps improve exercise capacity and reduce symptoms in PAH patients.