Vilitra contains vardenafil, a PDE5 inhibitor, which works by blocking the action of the enzyme phosphodiesterase type 5 (PDE5). PDE5 typically breaks down a chemical called cGMP, which is responsible for relaxing the smooth muscles and dilating blood vessels in the penis. By inhibiting PDE5, vardenafil helps to maintain higher levels of cGMP, promoting increased blood flow to the penis when sexually stimulated.
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