A Harvard Specialist shares his Ideas on testosterone-replacement therapy
An interview with Abraham Morgentaler, M.D.
It could be stated that testosterone is what makes men, men. It gives them their characteristic deep voices, large muscles, and facial and body 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. It also 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 about 1% a year, beginning in the 40s. As men get into their 50s, 60s, and beyond, they may start to have signs and symptoms of low testosterone such as reduced libido and sense of energy, erectile dysfunction, diminished energy, decreased muscle mass and bone density, and nausea. Taken together, these signs and symptoms are often called hypogonadism ("hypo" meaning low functioning and"gonadism" referring to the testicles). Yet it is an underdiagnosed problem, with only about 5% of those affected receiving treatment.
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 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 ailments and male reproductive and sexual problems. He's developed particular expertise in treating lower testosterone levels. In this interview, Dr. Morgentaler shares his perspectives on current controversies, the treatment plans he uses with his own patients, and why he believes specialists should rethink the potential connection between testosterone-replacement therapy and prostate cancer.
Symptoms go to my siteright hereclick this site and diagnosisWhat signs and symptoms of low testosterone prompt that the typical person 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 reduced sexual libido or desire, but another can be erectile dysfunction, and some other guy who complains of erectile dysfunction should get his testosterone level checked. Men can experience other symptoms, such as more difficulty achieving an orgasm, less-intense orgasms, a much lesser quantity of fluid from ejaculation, and a feeling of numbness in the manhood when they see or experience something which would normally be arousing.
The more of these symptoms you will find, the more probable it is that a man has low testosterone. Many physicians tend to dismiss those"soft symptoms" as a normal part of aging, however, they are often treatable and reversible by decreasing testosterone levels.
Aren't those the same symptoms that guys have when they're treated for benign prostatic hyperplasia, or BPH?
Not exactly. There are a number of medications that may lessen sex drive, such as the BPH drugs finasteride (Proscar) and dutasteride (Avodart). Those drugs may also reduce the amount of the ejaculatory fluid, no wonder. But a decrease in orgasm intensity usually does not go together with treatment for BPH. Erectile dysfunction does not ordinarily go along with it , though surely if somebody has less sex drive or less attention, it's more of a struggle to have a good erection.
How can you determine if a person is a candidate for testosterone-replacement therapy?
There are just two ways we determine whether someone has low testosterone. One is a blood test and the other one is by characteristic symptoms and signs, and the correlation between these two approaches is far from perfect. Normally men with the lowest testosterone have the most symptoms and guys with highest testosterone have the least. But there are some men who have reduced levels of testosterone in their blood and have no symptoms.
Looking at the biochemical numbers, The Endocrine Society* believes low testosterone for a total testosterone level of less than 300 ng/dl, and I believe that is a reasonable guide. However, no one really agrees on a number. It is similar to diabetes, where if your fasting sugar is over a certain level, they'll say,"Okay, you've got it." With testosterone, that break point is not quite as apparent.
| *Note: The Endocrine Society publishes clinical practice guidelines with recommendations for who should and should not receive testosterone treatment. |
Is complete testosterone the ideal thing to be measuring? Or should we be measuring something different?
This is 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 body. However, about half of their testosterone that is circulating in the bloodstream is not readily available to cells. It's closely bound to a carrier molecule known as 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 cells. Though it's only a small portion of this total, the free testosterone level is a fairly good indicator of reduced testosterone. It is not perfect, but the correlation is greater than with total testosterone.
Endocrine Society recommendations outlinedThis professional organization recommends testosterone therapy for men who have both Therapy Isn't Suggested for men who have
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Do time of day, diet, or other factors affect testosterone levels?
For years, the recommendation has been to get a testosterone value early in the morning because levels start to drop after 10 or 11 a.m.. But the data behind that recommendation were drawn from healthy young men. Two recent studies demonstrated little change in blood glucose levels in men 40 and mature within the course of this day. One reported no change in typical testosterone until after 2 p.m. Between 2 and 6 p.m., it went down by 13%, a modest sum, and probably insufficient to affect identification. Most guidelines nevertheless say it's important to do the test in the morning, however for men 40 and over, it likely does not matter much, as long as they get their blood drawn before 5 or 6 p.m.
There are some very interesting findings about diet. By way of instance, it seems that individuals that have a diet low in protein have lower testosterone levels than men who consume more protein. But diet hasn't been studied thoroughly enough to make any clear recommendations.
Within the following article, testosterone-replacement therapy refers to the treatment of hypogonadism with exogenous testosterone -- testosterone that's manufactured outside the body. Depending upon the formula, treatment can lead to skin irritation, breast tenderness and enlargement, sleep apnea, acne, decreased sperm count, increased red blood cell count, and other side effects.
In a recent prospective study, 36 hypogonadal men took a daily dose of clomiphene citrate for at least three months. Within four to six months, all of the guys had increased levels of testosterone; none reported some side effects during the year they had been followed.
Because clomiphene citrate isn't approved by the FDA for use in males, little information exists regarding the long-term ramifications of taking it (such as the probability of developing prostate cancer) or whether it's more effective at boosting testosterone compared to exogenous formulations. But unlike exogenous testosterone, clomiphene citrate maintains -- and possibly enriches -- sperm production. That makes medication like clomiphene citrate one of just a few choices for men with low testosterone who wish to father children.
What kinds of testosterone-replacement therapy can be found? *
The oldest form is the injection, which we still use because it is inexpensive and since we reliably become good testosterone levels in almost everybody. The disadvantage is that a man should come in every few weeks to find a shot. A roller-coaster effect can also happen as blood glucose levels peak and then return to research.
Topical treatments help maintain a more uniform amount of blood testosterone. 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 on their skin. That restricts its usage.
The most commonly used testosterone preparation from the United States -- and also the one I start almost everyone off -- is a topical gel. The gel comes in tiny tubes or in a special dispenser, and you rub it on your shoulders or upper arms once a day. According to my experience, it tends to be consumed to great levels in about 80% to 85% of guys, but that leaves a substantial number who do not consume enough for this to have a favorable effect. [For specifics on several different formulations, see table below.]
Are there any drawbacks to using dyes? How much time does it take for them to work?
Men who begin using the implants need to come back in to have their testosterone levels measured again to be certain they're absorbing the proper amount. Our target is that the mid to upper assortment of normal, which usually means around 500 to 600 ng/dl. The concentration of testosterone in blood actually goes up quite quickly, in just several doses. I usually measure it after two weeks, although symptoms may not alter for a month or two.