A man “can do”, not only to be firm (can hard erection), but also to last (ejaculation latency long enough)! The inability to get a normal erection is often diagnosed as impotence, while short latency to ejaculate is a typical symptom of premature ejaculation, both of which belong to different types of male sexual dysfunction, from pathogenesis to treatment are different. “Viagra is the most commonly used drug to treat impotence, and there are three main types: Viagra, Cialis, and Aleida. However, Viagra is not the legendary “aphrodisiac” or “sex drug”, and taking Viagra does not cause or increase sexual desire. The actual “Viagra” is not a legendary “aphrodisiac” or “sex pill”. “The real function of Viagra is to increase blood flow to the penis to restore or improve erectile function when the sexual urge is present. In other words, it helps a man with sexual urges to accomplish a normal penile erection with the goal of treating impotence. Although some studies have shown that Viagra can extend the latency of ejaculation to some extent, the mechanism is unknown and may be related to the patient’s psychological factors. Theoretically, Viagra does not transform a “fast man” who ejaculates in seconds into a “fierce man” who does not ejaculate. Theoretically, Viagra does not transform a “fast man” who ejaculates in seconds into a “strong man” who does not emit. Therefore, if there is premature ejaculation, it should be combined with other drugs or therapies.