sildenafil

A selective inhibitor of cGMP-specific phosphodiesterase type 5 (PDE5); relaxes the muscle in the penis, resulting in greater blood flow and erection; used to treat male impotence; potentiates the hypotensive effects of nitrates.

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sil·den·a·fil sil-'den-ə-.fil n a drug that is used in the form of its citrate C₂₂H₃₀N₆O₄S·C₆H₈O₇ to treat erectile dysfunction in males, that by suppressing a phosphodiesterase enzyme also suppresses the enzyme's inhibitory effect on the hormone cyclic GMP, and that enables the cyclic GMP produced during sexual arousal to initiate the muscular and vascular changes which produce an erection see viagra

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n.

a drug administered orally for the treatment of erectile impotence. During sexual stimulation, it causes smooth muscle relaxation and increased blood flow to the corpus cavernosum of the penis, which results in erection. Side-effects include headache, facial flushing, dyspepsia, nasal congestion, and dizzinesss. Because of severe adverse reactions, the drug is contraindicated in patients taking nitrate-based drugs, such as glyceryl trinitrate. Trade name: Viagra.