A Harvard expert shares his thoughts on testosterone-replacement therapy
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 growth of the genitals at puberty, plays a role in sperm production, fuels libido, and contributes to normal erections. It also fosters the production of red blood cells, boosts mood, and aids cognition.
Over time, the testicular"machinery" which produces testosterone slowly becomes less powerful, and testosterone levels begin to drop, by approximately 1 percent per year, starting in the 40s. As guys get in their 50s, 60s, and beyond, they might begin to have signs and symptoms of low testosterone such as lower sex drive and sense of vitality, erectile dysfunction, decreased energy, reduced muscle mass and bone density, and anemia. Taken together, these signs and symptoms are often referred to as hypogonadism ("hypo" significance low working and"gonadism" speaking to the testicles). Yet it's an underdiagnosed issue, with just about 5% of those affected receiving treatment.
But little consensus exists on what constitutes low testosterone, when testosterone supplementation makes sense, or what risks patients face. Much of the current debate focuses on the long-held belief that testosterone can 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 diseases and male reproductive and sexual difficulties. He has developed particular experience in treating lower testosterone levels. In this interview, Dr. Morgentaler shares his views on current controversies, the treatment strategies he uses with his patients, and he believes specialists should rethink the potential link between testosterone-replacement therapy and prostate cancer.
Symptoms and diagnosisWhat symptoms and signs of low testosterone prompt that the average man to find a doctor?
As a urologist, I tend to see guys because they have sexual complaints. The primary hallmark of reduced testosterone is reduced sexual desire or libido, but another may be erectile dysfunction, and some other man who complains of erectile dysfunction should possess his testosterone level checked. Men may experience other symptoms, like more difficulty achieving an orgasm, less-intense orgasms, a much smaller quantity of fluid out of ejaculation, and a feeling of numbness in the manhood when they see or experience something that would normally be arousing.
The more of the symptoms there are, the more probable it is that a man has low testosterone. Many physicians often dismiss those"soft symptoms" as a normal part of aging, however, they are often treatable and reversible by decreasing testosterone levels.
Are not those the same symptoms that guys have when they're treated for benign prostatic hyperplasia, or BPH?
Not precisely. There are quite a few drugs which may lessen sex drive, such as the BPH drugs finasteride (Proscar) and dutasteride (Avodart). Those drugs may also decrease the quantity of the ejaculatory fluid, no question. However a decrease in orgasm intensity usually doesn't go along with therapy for BPH. Erectile dysfunction does not usually go together with it , 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 or not a man is a candidate for testosterone-replacement treatment?
There are two ways we determine whether somebody has reduced testosterone. One is a blood test and the other is by characteristic signs and symptoms, and the correlation between those two approaches is far from ideal. Generally guys with the lowest testosterone have the most symptoms and men with maximum testosterone have the least. But there are a number of men who have reduced levels of testosterone in their blood and have no signs.
Looking purely at the biochemical amounts, The Endocrine Society* considers low testosterone for a entire testosterone level of less than 300 ng/dl, and I think that is 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 is not quite as apparent.
| *Notice: The Endocrine Society publishes clinical practice guidelines with recommendations for Read Full Article who should and should Go Here not receive testosterone navigate here treatment. Is total testosterone the right point to be measuring? Or if we are measuring something else? This is just another area of confusion and good debate, but I don't think that it's as confusing as it is apparently in the literature. When most doctors learned about testosterone in medical school, they heard about total testosterone, or all the testosterone in the human body. However, about half of the testosterone that is circulating in the blood is not readily available to the cells. It is closely bound to a carrier molecule called sex hormone--binding globulin, which we abbreviate as SHBG. The available portion of overall testosterone is called free testosterone, and it's readily available to the cells. Even though it's only a little portion of this overall, the free testosterone level is a fairly good indicator of reduced testosterone. It's not perfect, but the correlation is greater than with total testosterone.
What forms of testosterone-replacement treatment are available? * The earliest form is an injection, which we use since it's cheap and because we faithfully get good testosterone levels in almost everybody. The disadvantage is that a person should come in every few weeks to find a shot. A roller-coaster effect can also happen as blood testosterone levels peak and return to research. [See"Exogenous vs. endogenous testosterone," above.] Topical treatments help maintain a more uniform amount of blood testosterone. The first kind of topical therapy was a patch, but it has a quite high rate of skin irritation. In 1 study, as many as 40% of people that used the patch developed a reddish area on their skin. That restricts its use. The most widely used testosterone preparation in the United States -- and also the one I begin almost everyone off with -- is a topical gel. There are just two brands: AndroGel and Testim. Based on my experience, it tends to be consumed to good degrees in about 80% to 85 percent of men, but that leaves a significant number who don't absorb sufficient for it to have a positive impact. [For specifics on various formulations, see table ] Are there any downsides to using gels? How long does it require them to get the job done? Men who start using the implants need to return in to have their testosterone levels measured again to make certain they're absorbing the right quantity. Our goal is that the mid to upper range of normal, which usually means approximately 500 to 600 ng/dl. The concentration of testosterone in blood really goes up quite fast, within a few doses. I normally measure it after 2 weeks, though symptoms may not change for a month or two. |