Posts Tagged ‘Thyroid’

Thyroid Hormone Disorders

// October 29th, 2010 // No Comments » // Hormones

The thyroid hormone thyroxine stabilizes the body’s metabolism and allows us to proceed on an even keel from day to day. Both excessive and inadequate thyroxine production (hyperthyroidism and hypothyroidism) can interfere with normal male sexual function.

The diagnosis of thyroid hormone disorders is usually not difficult in young men. Nervousness, palpitations, weight loss, tremor, and anxiety are manifestations of excessive thyroid hormone secretion. Fatigue, lethargy, slowness of thought, constipation, dry skin, cold intolerance, and a deepening voice are indications of hypothyroidism.

In the older man, symptoms are more subtle. An irregular heartbeat or unexplained weight loss may be a clue to an overactive thyroid. Memory loss can reflect inadequate thyroid production. In the middle-aged or older male, impotence may be the only obvious evidence of either condition.

Daniel, a fifty-two-year-old scientist, became impotent shortly after his divorce. His impotence was thought to be related to depression, and he had been seeing a psychiatrist for about one year. He had made some progress coping with his postdivorce depression, but his impotence persisted. Now he had a new problem — his left breast seemed to be growing.

Physical examination revealed a rapid pulse and a slightly enlarged thyroid. Daniel’s’ left breast was indeed large and glandular. His hands trembled. The thyroid enlargement, increased breast size, rapid pulse, and tremor suggested the possibility of an overactive thyroid. Blood tests provided confirmation. With treatment, thyroid hormone levels normalized, breast tissue receded, and potency was restored.

Disorders of thyroid function are generally not considered in the evaluation of impotence despite the fact that loss of libido (in about 70 percent of cases), impotence (in about 55 percent of cases), and breast enlargement (incidence unknown) are prominent in hyperthyroid men. It remains unclear exactly how hyperthyroidism predisposes men to these sexual problems. The hyperthyroid state does create several associated hormonal abnormalities. Testosterone production is adequate, but the body converts an inordinate amount of the testosterone into an estrogen hormone (estradiol). Correction of the hyperthyroidism diminishes the stimulus for excessive estrogen production and coincides with a return of libido and potency.

Men with underactive thyroids tend to have low serum testosterone levels. Correction of the hypothyroidism usually allows serum testosterone levels to return to normal, and sexual function resumes. Unfortunately, some hypothyroid patients experience failure of both thyroid and testicular hormone secretion. For those men, treatment with thyroid hormone and testosterone together is necessary to restore metabolic, and then sexual, health.

Men with hypothyroidism have one other hormone abnormality that contributes to their sexual dysfunction. Their serum prolactin levels are often elevated. For them, bromocriptine treatment is unnecessary; thyroid hormone alone will normalize prolactin levels. Once prolactin levels normalize, sexual function resumes.

More causes of impotence

// October 25th, 2010 // No Comments » // Impotence

Prescription Medications

Several drugs, specifically antihypertensives and antidepressants, as well as those commonly used to treat ulcers, can impair sexual responsiveness. Frequently, an adjustment in medication type or dosage is all that is needed to restore sexual potency.

Other Chemical Use

The chemicals in prescription medications are not the only substances responsible for disrupting male sexual function. Thus, the routine medical history contains questions concerning alcohol consumption, cigarette smoking, and use of marijuana, cocaine, and heroin. All these substances, when used in excess, can sabotage the operation of internal systems responsible for sex drive, erections, and ejaculation.


After taking the medical history, the doctor will perform a physical exam and will look for previously undiagnosed high blood pressure, diabetes, heart disease, and prostate problems. In addition, there are several unique features of the exam when sexual difficulties are involved.

Visual Field Exam

This test helps determine whether any loss of vision has occurred in the corner of the eyes. Pituitary tumors press on the portion of the eye nerves responsible for lateral or peripheral vision. They may also interfere with testosterone production, resulting in impotence.


The thyroid gland sits in the neck in front of the windpipe (trachea). The thyroid regulates virtually all the metabolic processes of the body and, when not functioning properly, can have a profound effect on desire and potency. The doctor can feel whether the thyroid is large or lumpy; patients whose impotence is caused by an over- or underactive thyroid (hyper- or hypothyroidism) have distortions in thyroid anatomy that can readily be detected.


As noted, adequate blood flow to the penis is essential for normal erections to occur. The easiest way to evaluate blood flow is to feel a patient’s pulse, particularly in the arteries in the groin and lower legs. Men with atherosclerosis or other problems that restrict blood flow have dampened pulses. If weak or absent pulses are found, blood flow to the genitals may also be inadequate.

Neurologic Exam

Signs of nerve damage (neuropathy) can be detected by simple maneuvers. Decreased sensation to the touch of a feather or a pinprick or sluggish or absent knee and ankle reflexes suggest a defect in the nerves that normally carry sensation and activate reflexes.

Penis and Testicles

The penis is checked for any firm, fibrous bands or distortions in shape that would indicate underlying Peyronie’s disease Testicular size is estimated. A substantial variation exists. Nevertheless, testicles less than 3.5 centimeters (one and one-half inches) are considered small. Truly atrophied testicles appear as pea-size nubbins in the scrotum.

It is also important to determine whether both testicles have descended fully into the scrotum. Normally, the testicles descend immediately before birth. Some testicles do not complete the migration; they become nonfunctional and can produce neither adequate amounts of testosterone nor sperm.

The length of the penis is rarely a factor in sexual dysfunction. For the very few men whose erect penis is too small for penetration, reconstructive surgery is possible.