Viagra is a brand (trade) name for the drug sildenafil. Sildenafil blocks the action of an enzyme known as cGMP-specific phosphodiesterase type-5 (PDE-5). This enzyme breaks down cGMP, a substance…
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Viagra is a brand (trade) name for the drug sildenafil. Sildenafil blocks the action of an enzyme known as cGMP-specific phosphodiesterase type-5 (PDE-5). This enzyme breaks down cGMP, a substance…