Boner drugs, short for phosphodiesterase type 5 inhibitor, AKA Viagra, Cialis, Levitra or Stendra. Works by inhibiting an enzyme called cGMP specific phosphodiesterase type 5, which regulates blood flow in the penis. Viagra was the first PDE5 Inhibitor, and it originally created as a drug to treat hypertension. It’s most interesting off-label use to date, other than by porn stars, has been by track and field athletes, and not just the pole vaulters. Athletes, including professional football players, are using it to increase blood flow to the lungs and muscles. They call it Vitamin V.