Testosterone is the hormone most responsible for sex drives and high libidos in men. It helps build muscle and bone mass. A decrease in testosterone can mean a decrease in sexual desire, fewer spontaneous erections, and a slightly lower sperm count.
Low testosterone levels in men are not uncommon. There is an age-related decline in testosterone levels, falling by about 1% each year. Approximately 1% of healthy young men have total serum testosterone levels below 250 ng/dl and approximately 20% of healthy men over 60 years old have serum testosterone levels below 250 ng/dl. However, despite the frequency of testosterone deficiency in aging men, significant questions remain over whom to evaluate, what to measure and how to treat.
Men with testosterone deficiency commonly experience sexual symptoms such as loss of libido, erectile dysfunction, and decreased volume of ejaculate. More generalized symptoms such as lack of energy, increased body fat, loss of motivation, inability to concentrate, depressed mood, sleep disturbance, fragile bones, and irritability are also frequently seen. Men that have low testosterone levels may notice loss of muscle strength, muscular aches, hot flushes, and slow beard growth.
Sexual symptoms (low libido and erectile dysfunction) correlate best with low testosterone levels, with generalized symptoms being substantially less specific. Unfortunately, even sexual symptoms have reduced specificity for testosterone deficiency due to the common occurrence of neurovascular causes of erectile dysfunction in aging men, as well as the many physical illnesses and psychosocial stresses that can result in low libido.
Physicians may suspect testosterone deficiency if they note loss of body hair, very small or “shrinking” testes, height loss, or reduced muscle bulk. Testosterone deficiency should also be considered in men with certain clinical disorders where the prevalence of testosterone deficiency is high or for whom therapy may be recommended. Such disorders include sellar mass or radiation to the sellar region; HIV-associated weight loss, end-stage renal disease, and maintenance hemodialysis; osteoporosis, or low-trauma fracture; infertlity and treatment with medications that affect testosterone production such as glucocorticoids or opioids. Testosterone deficiency is also very common in men with type 2 diabetes.
The evaluation of men with low testosterone levels is made confusing by the inherent complexity of testosterone physiology as well as problems with assays to measure testosterone. Testosterone in men is secreted almost solely from the testes. About 40-50% of testosterone is bound to sex-hormone-binding globulin (SHBG) and, as a result, is not accessible to receptors in target cells. Approximately 50-60% is loosely bound to albumin and the remaining 1-2% is in the Free State. The free testosterone and albumin-bound testosterone are felt to be “bioavailable”, i.e. available to act on receptors in target tissues.
Because of alterations in sex-hormone-binding-globulin (SHBG) and albumin, measurements of total testosterone (which includes all free and bound testosterone), may not always accurately reflect the bioavailable component. Nevertheless, most studies of testosterone deficiency rely on measurement of total testosterone and, in general, commercial assays for total testosterone are felt to be much more reliable than assays for free testosterone. Thus, measurement of total testosterone is the screening test of choice for men with low testosterone levels.
Testosterone levels demonstrate a circadian rhythm with the peak in the morning. Measurement of total testosterone should always take place in the morning (-8am). Although reported ranges for total testosterone are somewhat dependent on the specific lab and assay used, a total testosterone of greater than 320 ng/dl is considered normal. Men with a morning total testosterone greater than 320 ng/dl will not require further testing. Men with lower total testosterone levels should have the test repeated in a few weeks to avoid the possibility of temporary low testosterone due to stress or illness. It has been reported that 30% of men may have a normal testosterone on repeat measurements.
Men with total testosterone less than 200 ng/dl on more than one occasion have testosterone deficiency. Unfortunately, total testosterone levels in the range from 200-320 ng/dl are equivocal. Such men should have assessment of free or bioavailable testosterone. The gold standard for measurement of free testosterone is equilibrium dialysis, but this methodology is expensive and not widely available. Fortunately, calculated free testosterone (using total testosterone, albumin and SHBG) provides values nearly identical to free testosterone by equilibrium dialysis.
Other than men with equivocal (200-320 ng/dl) total testosterone levels, only men suspected of harboring altered levels of sex-hormone-binding-globulin should be screened (calculated) free or bioavailable testosterone. Sex-hormone-binding-globulin levels can be altered in a number of circumstances including aging, obesity, diabetes, thyroid disease, and HIV.
Treatment for testosterone deficiency can be offered to symptomatic men with low testosterone levels with the goal of maintaining secondary sex characteristics and improving sexual function, sense of well-being, and bone mineral density, provided that no contraindications to treatment exist. Testosterone therapy is not recommended for men with prostate cancer, hematocrit above 50%, untreated severe obstructive sleep apnea, severe lower urinary tract symptoms, or severe heart failure. A digital rectal exam (DRE) as well as serum PSA measurement should be performed prior to the initiation of testosterone therapy.
Men with palpable prostate abnormalities should have further urologic evaluation before testosterone is considered.
Testosterone supplementation is an option for men experiencing low testosterone. It is usually given by transdermal gel or patch, or by intramuscular (IM) injection. Testosterone gels are applied to nonscrotal skin once daily are preferred by most men. They are convenient, easily titratable and maintain steady day-to-day testosterone levels. However, gels are more expensive than other testosterone treatments. There is also the risk of potential transfer of testosterone to a sexual partner or child by direct skin-to-skin contact.
Testosterone patches are applied nightly to the hairless skin of the upper back, arm, or thigh; nightly application provides the closest approximation of the normal circadian rhythm of testosterone. Skin irritation and rash at the site of patch application is not rare; a low-dose triamcinolone cream applied prior to patch placement can reduce skin irritation without affecting testosterone absorption.
Intramuscular testosterone was the major mode of testosterone treatment prior to the introduction of patches and gels. Intramuscular injections of testosterone enanthate or cypionate may be administered weekly (75-100 mg) or, more commonly, every 2 weeks (150-200 mg). With this formulation, the testosterone peaks within a few days of administration and then slowly decline over the following 2 weeks. Its major drawback – in addition to the need for injection – is that men may develop fluctuating symptoms associated the peaks (hyperactivity) and valley (fatigue, depression) of testosterone. Nevertheless, intramuscular testosterone remains a common treatment for testosterone deficiency, particularly when cost is a factor or when men cannot achieve adequate serum levels with gels or patches.
It is important to recognize that recommendations regarding testosterone therapy are primarily based on short-term studies. The risks and benefits of long-term testosterone treatment are, unfortunately, unknown. Finally, there are some evidence-based ways to increase testosterone levels naturally, which includes exercising, taking vitamin and mineral supplements, minimizing stress and cortisol levels, and most importantly, taking all-natural male enhancement supplements like the Epiq Nights product which is the most powerful natural male enhancement pill on the market.