Men with sexual dysfunction often question whether they should have their testosterone level checked. Since there are a vast number of causes for this complaint, including advanced age, obesity, sedentary lifestyle, cigarette smoking, medications, heart disease, diabetes, anxiety, depression, and recreational drug use, it is very important to first assess whether the symptoms are consistent with testosterone deficiency. These include low sexual drive, decreased morning erections, loss of body hair, enlargement of breast tissue, and shrinkage of testicular tissue. Your doctor may also find you have low bone density, another common sign.
What causes low testosterone? Most commonly this is an age-related phenomenon. Testosterone levels decline with age at a rate of 1-2% per year, so deficiency most commonly manifests after age 50. There can also be an underlying problem with the glands in the brain that stimulate testosterone production (pituitary gland, hypothalamus), though this is less common.
Testosterone therapy can improve low libido and erectile dysfunction in men who have confirmed testosterone deficiency, based on symptoms and lab results. However, if testosterone levels are normal, studies have not shown that testosterone therapy provides any of these benefits.
There are many different formulations of testosterone replacement, the most popular being gels. There is a risk of skin transfer of the medication, leading to secondary exposure to it. It is therefore important to remember the following precautions when using gels: wash hands thoroughly after application, avoid skin contact with others till gel has dried, avoid getting the site wet for approximately 5 hours after application, and keep the application site covered with clothing. Other modalities of testosterone therapy include patch (short-acting, applied daily), and injection and implant (longer-acting).
Unfortunately testosterone therapy does pose some health risks, and anyone who is considering therapy should be aware of these. Most recently, the FDA issued a warning regarding the increased risk of blood clots. The FDA is also currently investigating the cardiovascular safety of testosterone use. Other known adverse effects include local reactions at the site of application, increased red blood cell count (which itself increases the risk of blood clots, stroke, and heart attack), acne, sleep apnea, fluid retention, and infertility.
Resources:
Heidelbaugh, Joel. Management of Erectile Dysfunction. Am Fam Physician. 2010 Feb 1;81(3):305-312
Margo, Katherine and Winn, Robert. Testosterone Treatments: Why, When, and How? Am Fam Physician. 2006 May 1;73(9):1591-1598.
Rhoden EL, Morgentaler A. Risks of Testosterone-Replacement Therapy and Recommendations for Monitoring. N Engl J Med 2004; 350:482-492 January 29, 2004
