In folklore, impotence (medical term for penile erectile dysfunction) and premature ejaculation are twin brothers, and when it comes to poor sexual function, people think of “impotence and premature ejaculation”. However, for many gay men, when they have sexual function problems, they can’t distinguish whether they are impotent or premature ejaculation, and when they visit the clinic, they “mislead” the doctor with their wrong judgment, making some doctors “duped”. In fact, it is quite simple to distinguish between the two. If the patient ejaculates soon after the penis becomes erect and then the penis weakens, then it is premature ejaculation; if the penis cannot become erect or cannot maintain an erection for sexual intercourse, then it is “impotence”. It is worth mentioning that in some patients, ejaculation occurs as soon as they receive sexual stimulation when the penis is not yet erect, and this is severe premature ejaculation, not erectile dysfunction.