Testosterone is an androgen, or male hormone, that regulates sexual function in men and, to a lesser extent, in women. It triggers the development of gender-specific features such as a deep voice, body and facial hair and genitalia. It also plays a role in the function of vital organs such as your muscles, heart, bones, blood vessels and brain. Testosterone production starts in the pituitary gland, which secretes a hormone known as luteinizing hormone, or LH. When your testosterone level is low, your pituitary gland sends out more LH. Your adrenal glands and your testicles respond by producing testosterone and sending it into the bloodstream.
Step 1
Talk with your doctor. He may order a testosterone test to determine the cause of delayed or early puberty, diminished sex drive, erectile dysfunction or infertility. You may also be sent for a testosterone test to rule out more serious problems, such as a tumor in your testicle or disorders of your pituitary gland, according to Lab Tests Online.
Step 2
Share your medical history. According to the University of Michigan Health System, testosterone levels may not be accurate if you're taking testosterone supplements, some seizure drugs, corticosteroids medicines, such as prednisone, a diuretic called aldactone, barbiturates or digoxin, a common heart medication. Thyroid disorders can also influence your lab results.
Step 3
Go to a medical laboratory. According to Lab Tests Online, there's no special preparation required for a testosterone blood level test.
Step 4
Review results with your doctor. Testosterone levels are lowest during childhood, highest during adolescence and early adulthood and then drop about 1 percent a year after 30 years of age. The University of Michigan Health System publishes an online table of testosterone levels showing that a male infant should have less than 30 nanograms/deciliter, or ng/dL, in his blood. From 10 to 13 years of age, a boy should have a testosterone level of 1 to 619 ng/dL. Teens between the ages of 14 and 15 years typically have 8 to 53 ng/dL of testosterone in their blood, while 16 to 19-year-olds average 200 to 970 ng/dL. If you're in your 20s or 30s, a normal testosterone level is somewhere between 270 and 1,080 ng.dL. From 40 to 59 years of age, expect to run between 350 and 890 ng/dL. From 60 years and up, men should have a testosterone level of 350 to 720 ng/dL.
Step 5
Discuss treatment options. If your body doesn't produce enough testosterone, your doctor may order testosterone supplements. However, the National Institute on Aging says, "Except for a relatively few younger and older men with extreme deficiencies, testosterone treatment is not deemed appropriate for most men at this time." There is little evidence of the long-term safety of supplemental testosterone, and some concern that it may increase your risk of prostate cancer.
