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Document for the general public

Definition of sexual health according to the world health organization

The World Health Organization (WHO) defines sexual health as a basic human right that includes the ability to enjoy and control sexual behavior and reproductive function based on personal and social values.1 This definition implies that individuals are free to express their sexuality without fear, shame, guilt, false beliefs, or other factors that may harm sexual relationships. It also implies that one should be free from organic diseases and other deficiencies that interfere with sexual and reproductive function.

What is erectile dysfunction (ED)?

ED, formerly called impotence, is defined as the persistent inability to attain and sustain an erection sufficient for satisfactory sexual intercourse.2 This definition, therefore, excludes disorders of sexual desire, ejaculation, and orgasm.

Although ED is a benign disorder, it has significant effects on the quality of life of those with the disorder and their partners.3 Sexual potency is typically associated with virility and manhood; having ED may affect a man's self-esteem and feeling of worth.2 In addition, religious and cultural aspects of lifestyles play an important role in how ED is perceived and may make many men reluctant to talk about or seek treatment for a disease that carries negative social connotations. Often, the general public regards this problem as a natural consequence of aging and there is a lack of vital information and education on sexual matters.

Are many men affected?

The incidence of ED is greater than expected, and according to the Epidemiologia de la Disfuncion Erectil Masculina (EDEM) Study conducted in Spain, the disease affects 12% of the male population between 25 and 70 y of age.4 This is equivalent in absolute terms to approximately 2 million men. It is estimated that worldwide more than 150 million men have ED;5 however, according to the results of the EDEM study, only 18% of affected men in Spain see a physician for ED.

The incidence of ED increases with age and with the presence of concomitant diseases, which may also occur more frequently with age, such as diabetes, high blood pressure, lipid disorders, and many other factors.2

Normal function of the penis

The penis is composed of three tubular structures: two corpora cavernosa and the corpus spongiosum. The urethra is a tube that runs inside the corpus spongiosum and connects the bladder to the outside, allowing the passage of urine and semen. The corpora cavernosa are two sponge-like structures that become rigid during erection when filled with blood. Blood flows into the corpora cavernosa through the cavernous arteries. There is about seven or eight times more blood in the penis when it is erect than when it is flaccid.6

The process that leads to penile erection is usually initiated in the brain after a sexual stimulus (eg, tactile, visual, olfactory, auditory, or psychological). This nerve impulse travels from the brain to the penis, causing the arteries to dilate and allowing blood to enter into the corpora cavernosa. At the same time, veins on the surface of the penis are compressed, preventing blood from flowing out. After ejaculation occurs and the erotic stimulus ends, the arteries contract, the veins dilate and the erection gradually subsides.7

In addition to erections that occur after an erotic stimulus, erections also occur during rapid eye movement sleep. There are three to five episodes during a normal night that last about 30–60 min each. This is why men sometimes wake up with an erection. Both nocturnal erections and those provoked by a sexual stimulus help to maintain normal penile function by ensuring adequate oxygenation; thus, regular oxygenation of the penis through sexual or nonsexual erections is beneficial for normal sexual function.8

Problems with erection

There are many problems, both physical and psychological, that can affect normal functioning of the penis. Physical or organic problems may include aging, certain illnesses (eg hypertension, diabetes), accidents, smoking, certain operations, alcohol and drug abuse, and the use of certain medications.

Aging: The aging process changes a man's sexual response but does not cause ED by itself. Just as a person is able to walk throughout his lifetime, he should also be able to have sexual relations. As men age, they can expect that certain changes will occur in their sex life. For example, it may take them a little longer to achieve an erection or they may require more direct physical stimulation; however, ED is not an inevitable consequence of aging.

Diseases: As one ages, many common diseases may appear that can cause problems with erection, such as arteriosclerosis, hypertension, stroke, heart attack or angina pectoris, diabetes, and so on. Cancer, chemotherapy, surgical treatment of some cancers (prostate, bladder, or rectum), radiotherapy, and kidney or liver diseases may also cause ED. There may also be problems with thyroid hormones and testosterone, which plays a role in sexual desire. As a man ages, the amount of testosterone in the blood may decrease naturally, and this is one of the reasons men may have less sexual desire after they reach a certain age.

Drugs: About 200 drugs used to treat certain diseases (eg, high blood pressure, depression, stomach ulcer) may affect the ability to have an erection.9

Tobacco and alcohol: These substances may damage the nerves and arteries and cause a failure in erection. Quitting these toxic habits may improve erectile function.

Psychological or emotional problems: Psychological problems may play a significant role in the ability to achieve and maintain an erection, and are often underestimated. The anxieties of daily life may contribute to less frequent sexual relations and reduce the ability to perform successfully. Other possible psychological problems are shyness, insecurity about performing well, concerns about penis size, or fear of the relationship with the partner. Fear of failure during sexual activity is perhaps the most important problem because the man focuses his attention on getting an erection instead of enjoying other aspects of sex, which may cause difficulties in achieving an erection.

What to do when erectile problems occur

If you experience problems with erection, the first steps are to talk to your partner and see a physician. You should clearly describe your problem to your doctor and answer his or her questions honestly. Your doctor will confirm whether there is an erection problem, and he or she will investigate the cause by a physical examination, tests, or questionnaires. ED may sometimes be the first symptom of other underlying diseases.2

Your doctor will attempt to modify any factors (eg smoking, alcohol, medications) that may play a role in your erectile problems. Your physician will also treat any diseases (eg diabetes, high blood pressure) that could be the cause of ED. In many cases, specific treatment for ED will also be added. Your doctor may give you treatment directly or refer you to a specialist for further testing or more specific treatment options if the etiology of your ED is unclear.

Treatment options

There are medical and surgical treatments for ED. In addition, therapy—such as psychotherapy or sex therapy—may be helpful in treating ED when it has a psychological cause such as anxiety, depression, or relationship problems.

Oral treatment for ED has been available since 1998. Treatment with sildenafil citrate (Viagra®) helps the penis fill with blood and enable an erection, and has shown high efficacy and safety for the treatment of ED, regardless of its cause and severity.10, 11 Two new drugs, tadalafil (Cialis®)12 and vardenafil (Levitra®)13, 14 are now available in the United States and Europe, but more clinical experience is needed to further determine the effectiveness of these drugs. Apomorphine (Uprima®, Taluvian®) interacts with brain activity that is linked to sexual function, but its efficacy is limited.15

Oral therapy should be prescribed and supervised by a physician. If medication is not effective, or not tolerated, or contraindications exist for its use, the patient should continue to the second step of treatment. After an appointment with an andrologist, a treatment option that consists of administering drugs into the penis by patient self-injection may be prescribed. There are other treatment options such as vacuum devices or constriction bands, which may be useful in certain patients. If these treatments are not effective, the next step would be the surgical implantation of a penile prosthesis.

Recommendations on male sexuality

  1. 1

    Do not renounce your sexuality; it is a basic human right.

  2. 2

    ED is a common health problem recognized by the WHO. You are not alone, talk to your partner openly and without fear.

  3. 3

    Although erectile function (sexual potency) changes with age, it is never too late to see a doctor about ED.

  4. 4

    Maintain frequent and stable sexual activity; it has been shown to have a beneficial effect on erections.

  5. 5

    Do not smoke or drink excessively, exercise regularly, and ask your doctor if the drugs you are taking could be harmful for erection and if they can be changed.

  6. 6

    ED has multiple causes: it may have a psychological or organic cause, and both factors often coexist. It is not your fault that you have ED.

  7. 7

    ED may be the first symptom of many diseases. If you experience ED, you should see your doctor.

  8. 8

    Diabetes, high blood pressure, increased cholesterol, and smoking are the most common causes of ED. If you have any of these factors, you are more likely to develop ED.

  9. 9

    Minimally invasive treatments that have been proven safe and effective currently exist for this disorder. Do not be afraid.

  10. 10

    The most important advice that can be given is to see your doctor if you have symptoms of ED.


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Correspondence to I Moncada.

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Moncada, I. Document for the general public. Int J Impot Res 16, S7–S9 (2004).

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