It could be said that testosterone is what makes men, men. It gives them their characteristic deep voices, large muscles, and body and facial hair, differentiating them from girls. It stimulates the development of the genitals , plays a role in sperm production, fuels libido, and contributes to normal erections. Additionally, it fosters the production of red blood cells, boosts mood, and aids cognition.
Over time, the testicular"machinery" that makes testosterone gradually becomes less effective, and testosterone levels start to fall, by approximately 1 percent per year, beginning in the 40s. As men get into their 50s, 60s, and beyond, they may start to have symptoms and signs of low testosterone like reduced libido and sense of energy, erectile dysfunction, diminished energy, decreased muscle mass and bone density, and nausea. Taken together, these symptoms and signs are often referred to as hypogonadism ("hypo" significance low working and"gonadism" speaking to the testicles). Researchers estimate that the condition affects anywhere from two to six million men in the United States. Yet it's an underdiagnosed issue, with only about 5% of those affected undergoing therapy.
But little consensus exists about what constitutes low testosterone, when testosterone supplementation makes sense, or what dangers patients face. Much of the current debate focuses on the long-held belief that testosterone may stimulate prostate cancer.
Dr. Abraham Morgentaler, an associate professor of surgery at Harvard Medical School and the director of Men's Health Boston, specializes in treating prostate ailments and male reproductive and sexual difficulties. He's developed specific expertise in treating low testosterone levels. In this interview, Dr. Morgentaler shares his views on current controversies, the treatment plans he utilizes his own patients, and why he thinks experts should reconsider the possible connection between testosterone-replacement therapy and prostate cancer.Symptoms and diagnosis
What signs and symptoms of low testosterone prompt that the typical man to see a physician?
As a urologist, I have a tendency to see men since they have sexual complaints. The main hallmark of low testosterone is low sexual libido or desire, but another may be erectile dysfunction, and any man who complains of erectile dysfunction must possess his testosterone level checked. Men may experience different symptoms, such as more difficulty achieving an orgasm, less-intense orgasms, a much smaller amount of fluid out of ejaculation, and a sense of numbness in the penis when they see or experience something that would usually be arousing.
The more of these symptoms there are, the more probable it is that a man has low testosterone. Many physicians often discount these"soft symptoms" as a normal part of aging, however, they're often treatable and reversible by normalizing testosterone levels.
Aren't those the very same symptoms that men have when they're treated for benign prostatic hyperplasia, or BPH?
Not precisely. There are a number of drugs which may lessen sex drive, such as the BPH drugs finasteride (Proscar) and dutasteride (Avodart). Those drugs can also reduce the amount of the ejaculatory fluid, no wonder. But a reduction in orgasm intensity normally does not go together with treatment for BPH. Erectile dysfunction does not ordinarily go along with it either, though surely if somebody has less sex drive or less attention, it's more of a struggle to get a fantastic erection.
How do you decide whether a person is a candidate for testosterone-replacement therapy?
There are just two ways that we determine whether someone has low testosterone. One is a blood test and the other one is by characteristic signs and symptoms, and the correlation between those two approaches is far from perfect. Normally men with the lowest testosterone have the most symptoms and guys with highest testosterone have the least. However, there are some guys who have reduced levels of testosterone in their blood and have no symptoms.
Looking at the biochemical numbers, The Endocrine Society* believes low testosterone to be a entire testosterone level of less than 300 ng/dl, and I believe that's a sensible guide. But no one really agrees on a number. It's similar to diabetes, where if your fasting glucose is over a certain level, they will say,"Okay, you've got it." With testosterone, that break point isn't quite as clear.
|*Note: The Endocrine Society publishes clinical practice guidelines with recommendations for who should and shouldn't receive testosterone treatment. See"Endocrine Society click for info recommendations summarized." For a complete copy of the guidelines, pop over to this web-site log on to www.endo-society.org.
Is total testosterone the ideal thing to be measuring? Or should we be measuring something else?
This is another area of confusion and good discussion, but I don't think that it's as confusing as it appears to be from the literature. When most physicians learned about testosterone in medical school, they heard about overall testosterone, or all the testosterone in the body. But about half of the testosterone that's circulating in the bloodstream isn't available to the cells.
The available part of total testosterone is called free testosterone, and it is readily available to cells. Almost every lab has a blood test to measure free testosterone. Even though it's only a little fraction of the total, the free testosterone level is a pretty good indicator of low testosterone. It's not perfect, but the correlation is greater compared to testosterone.
What kinds of testosterone-replacement treatment are available? *
The earliest form is an injection, which we still use since it's cheap and because we faithfully become good testosterone levels in almost everybody. The disadvantage is that a person needs to come in every couple of weeks to find a shot. A roller-coaster effect can also happen as blood testosterone levels peak and return to research.
Topical therapies help preserve a more uniform level of blood glucose. The first form of topical treatment was a patch, but it has a quite high rate of skin irritation. In 1 study, as many as 40 percent of men who used the patch developed a reddish area in their skin. That limits its use.
The most commonly used testosterone preparation in the United States -- and also the one I begin almost everyone off with -- is a topical gel. The gel comes in tiny tubes or in a unique dispenser, and you rub it on your shoulders or upper arms once a day. Based on my experience, it has a tendency to be absorbed to good levels in about 80% to 85 percent of men, but leaves a significant number who don't consume sufficient for it to have a favorable impact. [For specifics on several different formulations, see table below.]
Are there any downsides to using gels? How long does it require them to work?
Men who begin using the implants need to come back in to have their testosterone levels measured again to be sure they're absorbing the proper quantity. Our goal is the mid to upper assortment of normal, which generally means approximately 500 to 600 ng/dl. The concentration of testosterone in the blood actually goes up quite fast, in just a few doses. I usually measure it after 2 weeks, even though symptoms may not alter for a month or two.