Sexual dysfunction: in detail

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.

Sexual arousal disorders were previously known as frigidity in women and impotence in men, though these have now been replaced with less judgmental terms. Impotence is now known as erectile dysfunction, and frigidity has been replaced with a number of terms describing specific problems with, for example, desire or arousal.

For both men and women, these conditions can manifest as an aversion to, and avoidance of, sexual contact with a partner. In men, there may be partial or complete failure to attain or maintain an erection, or a lack of sexual excitement and pleasure in sexual activity.

Sexual pain disorders affect women almost exclusively and are known as dyspareunia (painful intercourse) and vaginismus (an involuntary spasm of the muscles of the vaginal wall that interferes with intercourse). Dyspareunia may be caused by insufficient lubrication (vaginal dryness) in women.

It is unclear exactly what causes vaginismus, but it is thought that past sexual trauma (such as rape or abuse) may play a role. Another female sexual pain disorder is called vulvodynia or vulvar vestibulitis. In this condition, women experience burning pain during sex which seems to be related to problems with the skin in the vulvar and vaginal areas. The cause is unknown.

A man with erectile dysfunction

The problem of an inadequate erection is probably one of the biggest issues a man confronts. Most men experience erectile problems on occasion, but impotence, also called erectile dysfunction, is defined as "the persistent failure to develop and maintain erections of sufficient rigidity for penetrative sexual intercourse." Of course, men have other kinds of sexual problems including lack of desire and problems with ejaculation, yet impotence is the most common and troubling.

The creation of an erection is an extremely complicated cascade of events that requires many different things to happen. There are numerous chemical transmitters involved in this including epinephrine, norepinephrine, acetylcholine, prostaglandins and nitric oxide. The exact mechanism by which erection occurs is still unclear but we do know that the neural input from the brain is extremely important. Reflex erections, as seen in people with cord damage such as paraplegics, are often poor erections and not sustainable for prolonged periods of intercourse.

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.

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

Abnormal levels of certain hormones, such as testosterone, thyroid hormone and a pituitary hormone known as prolactin, can interfere with erections and sex drive (libido). This is an uncommon cause of erectile dysfunction.

Erectile dysfunction can occur suddenly or gradually. Some men slowly lose the firmness of their erections or how long the erections last. In other men, especially those whose impotence is largely caused by psychological factors, the problem may occur unpredictably and can improve at any time. Despite their difficulties with erections, men with impotence often continue to have normal orgasm and ejaculation.

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.

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.

The advises from medical professionals