PDE5 inhibitors are a class of medications commonly used to treat erectile dysfunction (ED). They work by blocking the action of phosphodiesterase type 5 (PDE5), an enzyme that regulates blood flow to the penis. By inhibiting PDE5, these drugs promote relaxation of smooth muscle tissue and increase blood flow to the penis, leading to improved erectile function. Popular PDE5 inhibitors include sildenafil (Viagra), tadalafil (Cialis), vardenafil (Levitra), and avanafil (Stendra). These medications are typically taken orally and are effective in helping men achieve and maintain erections during sexual activity. It's important to consult a healthcare provider before using PDE5 inhibitors.