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Sildenafil (Viagra)

Charles Drew University of Medicine and Science · FDA-approved active Small molecule

Sildenafil inhibits phosphodiesterase-5 (PDE-5) in the corpus cavernosum, increasing cyclic GMP levels and promoting smooth muscle relaxation and vasodilation.

Sildenafil inhibits phosphodiesterase-5 (PDE-5) in the corpus cavernosum, increasing cyclic GMP levels and promoting smooth muscle relaxation and vasodilation. Used for Erectile dysfunction, Pulmonary arterial hypertension, Benign prostatic hyperplasia symptoms.

At a glance

Generic nameSildenafil (Viagra)
SponsorCharles Drew University of Medicine and Science
Drug classPhosphodiesterase-5 (PDE-5) inhibitor
TargetPDE-5 (phosphodiesterase type 5)
ModalitySmall molecule
Therapeutic areaUrology / Sexual Health
PhaseFDA-approved

Mechanism of action

By blocking PDE-5, sildenafil prevents the breakdown of cyclic guanosine monophosphate (cGMP), allowing cGMP to accumulate. This leads to smooth muscle relaxation in penile tissue and increased blood flow to the corpus cavernosum, facilitating erection in response to sexual stimulation. The drug works within the nitric oxide-cGMP signaling pathway.

Approved indications

Common side effects

Key clinical trials

Primary sources

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SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results

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