This paper offers a multidimensional analysis of sildenafil citrate (Viagra), a molecule originally synthesized as an antianginal by Pfizer and repurposed for the treatment of erectile dysfunction following serendipitous findings from phase I trials. The study articulates six analytical axes: (i) the molecular genesis and mechanism of phosphodiesterase type 5 inhibition; (ii) the legal architecture of the monopoly, including pediatric evergreening, pay-for-delay agreements with Teva and Mylan, and the rollout of the licensed generic through Greenstone; (iii) the associated medical scandals—cardiovascular alerts, the multidistrict melanoma litigation, and the prescriber bribery network documented by whistleblower Peter Rost; (iv) the obstetric tragedy of the STRIDER trial and, conversely, the off-label neonatal utility in persistent pulmonary hypertension; (v) geopolitical externalities (use by the CIA in Afghanistan) and ecotoxicological externalities (bioaccumulation, genotoxicity, and behavioral disruption in aquatic fauna); and (vi) sociocultural implications in the medicalization of aging and the conservationist myths associated with Traditional Chinese Medicine. The review integrates regulatory, judicial, clinical, and ethnographic sources to show how a pharmacological innovation has transcended its original indications to reconfigure commercial, clinical, environmental, and symbolic dynamics on a global scale. Keywords: sildenafil; Viagra; PDE5; evergreening; STRIDER; ecotoxicology; medicalization.