PDE5 inhibitors are medications for the treatment of erectile dysfunction in men, scientifically known as phosphodiesterase type 5 inhibitors, which is an umbrella term for a class of medications, represented by the drug often referred to as Viagra. It improves the hardness of male penile erection to complete sexual intercourse. It acts on the vascular smooth muscle, can inhibit the activity of phosphodiesterase type 5, so that the smooth muscle diastole, the arterial smooth muscle of the penis can provide more blood supply after diastole, so as to promote the spongy body of the penis to fill with blood in order to achieve the state of rapid erection. Therefore, the commonly used clinical preparation is Viagra, which is a short-acting preparation, taken within half an hour before sex, can achieve a good erection through sufficient sexual stimulation, complete normal sex life, and improve the hardness of the patient’s penis erection.