Dr. Freas replied: "According to the American Medical Journal, the typical male erection lasts from 30 minutes to approximately 45 minutes. This may also vary from person to person due to (weight, height, etc.). The reason why a male should seek "immediate" medical attention for an erection lasting more than four hours is because the penis is essentially a sponge, mostly consumed of soft tissues. When a male is aroused, the blood flow is pumped into the penis & this is how an erection takes place. That's how the slang term "hard" was created. If blood flow lasts that long in an organ, there is great concern for the heart. Blood could be trapped in the penis and there could even be a clot possible near this organ, or worse, trapped someweher nearer the heart. Doctors usually have to aide the individual in giving IV treatments of certain types of medication which will bring the erection down slowly, thus reassuring proper flow of blood and circulation back to the heart. If blood returns to quickly, it could have the potential to loosen a clot, which in turn casues strokes, heart attacks, coronaries, and the like. No, you're absolutely correct, this is no laughing matter, and should be taken very seriously. That's why when a couple is planning on having a family or engaging in a sexual relationship, it is very wise to see your physician to have a full workup taken, blood drawn, tests done, including a stress test if you're over 40 yrs old, colonoscopy, and other similar tests. That way, when you go to plan for the future, you won't be taken by surpise should something be wrong. Also, the earlier detected, the better you can plan for a healthier tomorrow. I hope this was some assistance to you. Best of luck. Cheero."