Physical factors include drugs (alcohol, nicotine, narcotics, stimulants, antihypertensives, antihistamines, and some psychotherapeutic drugs); injuries to the back, problems with an enlarged prostate gland, problems with blood supply, nerve damage (as in spinal cord injuries); or disease (diabetic neuropathy, multiple sclerosis, tumors, and, rarely, tertiary syphilis); failure of various organ systems (such as the heart and lungs); endocrine disorders (thyroid, pituitary, or adrenal gland problems); hormonal deficiencies (low testosterone, estrogen, or androgens); and some birth defects.

Sexual dysfunction disorders are generally classified into four categories: sexual desire disorders, sexual arousal disorders, orgasm disorders, and sexual pain disorders.

Sexual desire disorders or decreased libido can be caused by a decrease in normal estrogen (in women) or testosterone (in both men and women) production. Other causes may be aging, fatigue, pregnancy, medications (such as the SSRIs) or psychiatric conditions, such as depression and anxiety.

Orgasm disorders are a persistent delay or absence of orgasm following a normal sexual excitement phase. The disorder can occur in both women and men. Again, the SSRI antidepressants are frequent culprits -- these can delay the achievement of orgasm or eliminate it entirely.

Sexual dysfunctions are more common in the early adult years, with the majority of people seeking care for such conditions during their late twenties through thirties. The incidence increases again in the geriatric population, typically with gradual onset of symptoms that are associated most commonly with medical causes of sexual dysfunction.

Sexual dysfunction is more common in people who abuse alcohol and drugs. It is also more likely in people suffering from diabetes and degenerative neurological disorders. Ongoing psychological problems, difficulty maintaining relationships or chronic disharmony with the current sexual partner can also interfere with sexual function.

An erection occurs when the nervous system activates a rapid increase in blood flow. The vascular muscle in the spongy area becomes engorged with blood and the outflow of blood is cut off. An erection can occur as a reflex as we see in spinal cord patients, or can be caused by psychogenic (originating in the mind) stimulation. Numerous sexual stimuli are processed by the brain and transmitted to the penis via the nervous system.

In order to increase the size of an erection, there must be an increase in blood flow and, at the same time, the blood has to be prevented from leaving the penis.

Erectile dysfunction, also called impotence, means that a man's penis doesn't get hard enough to have intercourse. The man cannot get or maintain an erection. This condition affects approximately 30 million men in the United States. Erectile dysfunction is not the same as premature ejaculation, the inability to ejaculate (retarded ejaculation) or infertility.)

Because erections are caused by the buildup of blood in the shaft of the penis, poor blood flow in the penis can result in problems with erections. Damage to blood vessels can be caused by hardening of the arteries (atherosclerosis) or from trauma. Vascular disease is believed to be the most common medical cause of erectile dysfunction.

Many medications cause problems with sexual function, including drugs for high blood pressure, depression, heart disease and prostate cancer.

There are many effective treatments for erectile dysfunction. The most popular option is a class of drugs called phosphodiesterase type 5 (PDE5) inhibitors, which includes sildenafil (Viagra), vardenafil (Levitra) and tadalafil (Cialis). These drugs, taken in pill form from zero to 60 minutes before sexual activity, work in approximately 70 percent of men, though they are less effective in men with neurological causes of erectile dysfunction such as nerve damage from prostate surgery, diabetes or spinal cord injury.

Sildenafil (Viagra), vardenafil (Levitra) and tadalafil (Cialis) drugs can cause minor side effects such as flushing and headache, but they have been shown to be safe in most men, including those with heart disease. However, these drugs can interact with other medications and cause dangerously low blood pressure. In particular, they should never be taken with nitroglycerin or other nitrate medications commonly used to treat heart disease. Men with enlarged prostates who take alpha-blocker drugs such tamsulosin (Flomax) or doxazosin (Cardura) should probably avoid PDE5 drugs.

Men who do not benefit from medical or psychological treatment often have success with mechanical or prosthetic devices. External products, known as vacuum erection devices, are safe and highly effective, but many men and their partners find them unappealing. Another option is a surgically placed penile implant. However, because implants require surgery (with the risk of surgical complications), only 10 percent of men with erectile dysfunction choose this option. Vascular (blood vessel) surgery sometimes is recommended for young, healthy men who develop impotence after trauma to the groin.

Terms and definitions on this page

Anxiety

• A state of uneasiness and apprehension, as about future uncertainties.


• Worry or tension in response to real or imagined stress, danger, or dreaded situations. Physical reactions such as fast pulse, sweating, trembling, fatigue, and weakness may accompany anxiety.

Impotence

• The inability to achieve and sustain penile erections.

Thyroid

• A gland in the throat that produces hormones that regulate growth and metabolism.


• A large gland in the neck that functions in the endocrine system. The thyroid secretes hormones that regulate growth and metabolism.

Antihistamines

• A drug used to counteract the physiological effects of histamine production in allergic reactions and colds.

Antihypertensives

• Reducing or controlling high blood pressure.

Depression

• In psychiatry, a symptom of mood disorder characterized by intense feelings of loss, sadness, hopelessness, failure, and rejection.

Ejaculation

• The expulsion of seminal fluid from the urethra of the penis during orgasm.


• The process of ejecting semen from the penis, and is usually accompanied by orgasm as a result of sexual stimulation.

Erection

• The firm and enlarged condition of a body organ or part when the erectile tissue surrounding it becomes filled with blood, especially such a condition of the penis or clitoris.

Estrogen

• Any of several steroid hormones produced chiefly by the ovaries and responsible for promoting estrus and the development and maintenance of female secondary sex characteristics.


• Any one of a group of hormones synthesized by the reproductive organs and adrenal glands in females and, in lesser quantities, in males.

Frigidity

• The state of marked or abnormal sexual indifference.


• Sexual unresponsiveness (especially of women) and inability to achieve orgasm during intercourse.

Hormone

• A substance, usually a peptide or steroid, produced by one tissue and conveyed by the bloodstream to another to effect physiological activity, such as growth or metabolism.

Orgasm

• The peak of sexual excitement, characterized by strong feelings of pleasure and by a series of involuntary contractions of the muscles of the genitals, usually accompanied by the ejaculation of semen by the male.


• The highest point of sexual excitement, marked by strong feelings of pleasure and marked normally by ejaculation of semen by the male and by vaginal contractions within the female.

Paraplegics

• Complete paralysis of the lower half of the body including both legs, usually caused by damage to the spinal cord.

Penis

• The male organ of copulation in higher vertebrates, homologous with the clitoris. In mammals, it also serves as the male organ of urinary excretion.


• The organ of the male reproductive system through which semen passes out of the body during sexual intercourse. The penis is also an organ of urination.

Prostate

• Gland in males that surrounds the urine tube (urethra) at the base of the bladder.


• A firm partly muscular chestnut sized gland in males at the neck of the urethra; produces a viscid secretion that is the fluid part of semen.

Stress

• A state of extreme difficulty, pressure, or strain.


• A physical and psychological response that results from being exposed to a demand or pressure.

Testosterone

• A white crystalline steroid hormone, C19H28O2, produced primarily in the testes and responsible for the development and maintenance of male secondary sex characteristics. It is also produced synthetically for use in medical treatment.

Directory with links to popular consumer products and services.