if you experience an erection lasting more than 4 hours.

Erectile dysfunction is a common problem, and for most patients, these drugs are safe. But, as the ads all say, “Seek immediate medical help ”

Glenn D. Braunstein, M.D., 

Talk about making a silk purse out of a sow’s ear. The manufacturers to Viagra, Cialis and Levitra have taken an FDA-mandated warning and turned it into a marketing coup. After all, in addition to flowers and chocolates, what better present can you give your Valentine than a night of pleasure from your 4-plus hour erection?


 Unfortunately, should you experience this prolonged penile engorgement, a condition called priapism, it may be the last erection that you ever have.

Erections occur when the muscle cells that surround the small arterial blood vessels in the penis relax, allowing blood to flow into the penis, which then enlarges and closes off the veins that drain the blood from the penis that keeps it erect. Ejaculation results in less blood flowing to the penis, releasing the pressure on the veins and thereby allowing the blood to flow out. Viagra (sildenafil), Cialis (tadalafil) and Levitra (vardenafil) are members of a drug class called phosphodiesterase type 5 (PDE5) inhibitors. These drugs prolong the relaxation of the muscles around the penile blood vessels, keeping the blood in the penis.

Priapism is defined as a penis that remains erect for more than 4 hours despite the absence of physical or psychological stimulation. The term is derived from the Greek fertility god, Priapus, who was known for his large, permanent erection. Priapism is very rare with any of these PDE5 inhibitors, and, in most instances, is mild. The risk is increased in men using other medications for erectile dysfunction, such as penile injections of Caverject (alprostadil). Use of psychotropics, phentolamine, amphetamines and cocaine also can increase the risk. Individuals with sickle cell disease, multiple myeloma and leukemia are also at increased risk of priapism when using these drugs.

If priapism is not treated rapidly, permanent erectile dysfunction (i.e. impotence), penile disfigurement, or loss of part or the entire penis may result. Fortunately, most treatments are effective if the individual sees a physician rapidly and includes use of medications, aspiration and irrigation of the stagnated blood in the penis, and, for severe priapism, surgical shunting of the blood from one part of the penis to another.

The more common side effects of these drugs are headache, upset stomach, facial flushing, and a stuffy or runny nose. These are self-limited nuisances and not serious.

These comments are certainly not meant to scare anybody off from using these medications. Erectile dysfunction is a common problem, and for most patients, these drugs are safe and effective, and have restored a healthy sex life to millions of couples. But, as the ads all say, “Seek immediate medical help if you experience an erection lasting more than 4 hours.”