Many a man has dreamed of being a god in the bedroom. And thanks to sexual mythology spawned by the porn industry and media, long-lasting sex is a huge part of that daydream.

But there's such a thing as lasting too long. Priapism is the medical term for an erection that lasts way longer than any man would seriously want — hours, or even days. And it is a nightmare.

No mortal in his right mind wants to be like Priapus, the Greek fertility god for whom the condition is named.

It's a tireless topic for comedians, but priapism is no laughing matter.

A healthy erection is a matter of blood flow. Ischemic (meaning "lack of oxygen") priapism occurs when blood does not drain as it should. It gets trapped in the penis, depletes oxygen levels and results in unwanted consequences.

Dire for oxygen themselves, the red blood cells become stiff, making proper blood drainage even more difficult. This can cause major complications: Oxygen-poor blood can become toxic to tissues, damaging if not destroying them. This can result in scarring, disfigurement or permanent erectile dysfunction if the condition is not treated within four to six hours of onset.

So what causes this malfunction? It’s typically assumed that this often painful and tender condition is due to sexual thoughts, stimulation or desire that “can’t get no satisfaction.” But it’s not.

Most case of ischemic priapism can be explained medically:

— Drug injections for treating erectile dysfunction (ED) — especially if he uses more than what’s prescribed;

— Oral therapy medications for ED;

— Using or misusing medications, like anti-depressants, anti-anxiety, anti-psychotics, or blood thinners;

— Illicit drug use, including marijuana, ecstasy or cocaine;

— Recreational use of ED drugs or excessive alcohol consumption;

— Medical conditions, particularly those that lead to blood cells losing their flexibility and mobility, such as sickle-cell anemia, or diseases that cause the blood to clot easier, like diabetes;

— Trauma to the pelvic or genital area, such as a ruptured artery from a penile injury that prevents normal circulation;

— Spinal cord injury;

— Poisonous venom from black widow spider bites;

— Carbon monoxide poisoning;

— Cancers that affect the penis and its blood flow;

— Spanish fly, a hazardous “aphrodisiac.”

While priapism is uncommon, it is an emergency. Seek care pronto if you notice excess swelling, feel pain, or have an unusually long erection. Likewise, if you experience multiple persistent, unwanted erections, generally lasting 2-3 hours — known as stuttering priapism — see your physician.

Do not try to treat priapism on your own. This is an emergency situation that requires professional attention. Treatment will depend on the suspected cause, and may include:

— Medications to decrease blood flow to the penis;

— Ice packs to reduce swelling;

— Aspiration: a needle is inserted and the penis is drained of excess blood to reduce swelling and pressure, often followed by a saline flush of the penile blood vessels;

— Surgical ligation to repair any ruptured artery;

— Surgical shunt, where a passageway is inserted to “divert” blood flow, allowing normal circulation to resume;

— Intracavernous injection to narrow the arteries, reducing blood flow and alleviating swelling.

When treated in a timely manner, the prognosis is very positive. To prevent recurrence — or occurrence in general — options include avoiding triggers, hormone treatment, changing medications, using prescription muscle relaxants or self-injections of phenylephrine, or managing the physical conditions at the root of priapism.

Priapism can happen to males of any age, including newborns. It’s actually most common in boys ages 5-10 and men ages 20-50. Legend holds that Priapus was cursed with impotence while still in his mother’s womb. To make sure that doesn't happen to you, get help immediately if faced with this situation.

Dr. Yvonne K. Fulbright is a sex educator, relationship expert, columnist and founder of Sexuality Source Inc. She is the author of several books including, "Touch Me There! A Hands-On Guide to Your Orgasmic Hot Spots."

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