A Harvard Specialist shares his thoughts on testosterone-replacement therapy
A meeting with Abraham Morgentaler, M.D.
It might be said that testosterone is what makes guys, guys. It gives them their characteristic deep voices, large muscles, and facial and body hair, distinguishing them from girls. It stimulates the development of the genitals at puberty, plays a role in sperm production, fuels libido, and contributes to normal erections. Additionally, it boosts the production of red blood cells, boosts mood, and aids cognition.
As time passes, the "machinery" which makes testosterone slowly becomes less powerful, and testosterone levels start to drop, by approximately 1 percent a year, starting in the 40s. As guys get into their 50s, 60s, and beyond, they might start to have signs and symptoms of low testosterone like reduced libido and sense of vitality, erectile dysfunction, diminished energy, decreased muscle mass and bone density, and anemia. Taken together, these symptoms and signs are often called hypogonadism ("hypo" meaning low working and"gonadism" referring to the testicles). Yet it is an underdiagnosed issue, with just about 5% of these affected receiving treatment.
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 difficulties. He's developed particular experience in treating low testosterone levels. In this interview, Dr. Morgentaler shares his perspectives on current controversies, the treatment plans he uses with his patients, and why he believes experts should reconsider the potential link between testosterone-replacement treatment and prostate cancer.
Symptoms and diagnosisWhat signs and symptoms of low testosterone prompt that the typical man to find a doctor?
As a urologist, I have a tendency to see guys since they have sexual complaints. The primary hallmark of reduced testosterone is low sexual libido or desire, but another may be erectile dysfunction, and any man who complains of erectile dysfunction should get his testosterone level checked. Men can experience other symptoms, such as more trouble achieving an orgasm, less-intense orgasms, a lesser quantity of fluid from ejaculation, and a sense 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 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 guys have when they're treated for benign prostatic hyperplasia, or BPH?
Not exactly. There are quite a few medications that may lessen sex drive, such as the BPH medication finasteride (Proscar) and dutasteride (Avodart). Those drugs can also decrease the amount of the ejaculatory fluid, no wonder. However a reduction in orgasm intensity normally doesn't go along with treatment for BPH. Erectile dysfunction does not usually go together with it , though certainly if a person has less sex drive or less attention, it is more of a challenge to get a good erection.
How do you decide if or not a person is a candidate for testosterone-replacement therapy?
There are two ways that we determine whether somebody has reduced 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 ideal. Normally guys with the lowest testosterone have the most symptoms and men with highest testosterone have the least. But there are some guys who have reduced levels of testosterone in their blood and have no signs.
Looking at the biochemical numbers, The Endocrine Society* considers low testosterone to be a total testosterone level of less than 300 ng/dl, and I believe that is a sensible guide. However, no one really agrees on a few. It is similar to diabetes, where if your fasting glucose is above a certain level, they'll say,"Okay, you've got it." With testosterone, that break point is not quite as clear.
| *Note: The Endocrine Society publishes clinical practice guidelines with recommendations for who should and should not receive testosterone therapy. Watch"Endocrine Society recommendations summarized." |
Is total testosterone the right point to be measuring? Or if we are measuring something different?
This is just another area of confusion and good discussion, but I don't think it's as confusing as it appears to be in the literature. When most doctors learned about testosterone in medical school, they learned about overall testosterone, or all of the testosterone in the human body. However, about half of their testosterone that is circulating in the blood isn't readily available to cells. It's tightly bound to a carrier molecule called sex hormone--binding globulin, which we abbreviate as SHBG.
The biologically available portion of overall testosterone is called free testosterone, and it's readily available to the cells. Almost every laboratory has a blood test to measure free testosterone. Though it's just a little portion of this overall, the free testosterone level is a pretty good indicator of low testosterone. It is not ideal, but the significance is greater than with total testosterone.
This professional organization recommends testosterone therapy for men who have both
- Low levels of testosterone in the blood (less than 300 ng/dl)
- symptoms of low testosterone.
Therapy Isn't Suggested for men who have
- Prostate or breast cancer
- a nodule on the prostate which may be felt during a DRE
- a PSA greater than 3 ng/ml without additional evaluation
- a hematocrit greater than 50% or thick, viscous blood
- untreated obstructive sleep apnea
- severe lower urinary tract symptoms
- class III or IV try this heart browse around this web-site failure.
Do time of day, diet, or other elements affect testosterone levels?
For years, the recommendation was to get a testosterone value early in the morning because levels begin to drop after 10 or 11 a.m.. However, the information behind that recommendation were attracted to healthy young men. Two recent studies demonstrated little change in blood testosterone levels in men 40 and mature over the course of the day. One reported no change in typical testosterone until after 2 Between 2 and 6 p.m., it went down by 13 percent, a modest sum, and probably not enough to influence identification. Most guidelines still say it is important to do the evaluation in the morning, however for men 40 and above, it likely doesn't matter much, provided that they obtain their blood drawn before 5 or 6 p.m.
There are a number of very interesting findings about dietary supplements. For instance, it appears that those who have a diet low in protein have lower testosterone levels than men who eat more protein. But diet hasn't been researched thoroughly enough to make any recommendations that are clear.
Exogenous vs. endogenous testosterone
Within this guide, testosterone-replacement therapy refers to the treatment of hypogonadism with adrenal gland -- testosterone that is produced outside the body. Depending upon the formula, treatment can lead to skin irritation, breast enlargement and tenderness, sleep apnea, acne, decreased sperm count, increased red blood cell count, and additional side effects.
Preliminary studies have shown that clomiphene citrate (Clomid), a drug generally prescribed to stimulate ovulation in women struggling with infertility, can boost the production of natural testosterone, also termed nitric oxide, in men. Within four to six months, all the guys had heightened levels of testosterone; none reported any side effects during the entire year they were followed.
Since clomiphene citrate isn't approved by the FDA for use in males, little information exists about the long-term ramifications of carrying it (including the probability of developing prostate cancer) or if it is more effective at boosting testosterone compared to exogenous formulations. But unlike exogenous testosterone, clomiphene citrate maintains -- and possibly enhances -- sperm production. This makes medication like clomiphene citrate one of just a few options for men with low testosterone who want to father children.
What kinds of testosterone-replacement therapy are available? *
The oldest form is the injection, which we still use since it is inexpensive and because we faithfully become good testosterone levels in nearly everybody. The disadvantage is that a person should come in every few weeks to get a shot. A roller-coaster effect can also happen as blood testosterone levels peak and then return to research. [Watch"Exogenous vs. endogenous testosterone," above.]
Topical treatments help maintain a more uniform level of blood testosterone. The first kind of topical treatment has been a patch, but it has a very high rate of skin irritation. In one study, as many as 40% of people that used the patch developed a reddish area on their skin. That limits its use.
The most commonly used testosterone preparation from the United States -- and also the one I begin almost everyone off -- is a topical gel. According to my experience, it has a tendency to be absorbed to good levels in about 80% to 85% of men, but that leaves a substantial number who don't consume sufficient for this to have a favorable impact. [For details on various formulations, see table below.]
Are there any drawbacks to using gels? How long does it take for them to work?
Men who start using the gels have to return in to have their own testosterone levels measured again to be certain they are absorbing the proper amount. Our target is the mid to upper range of normal, which usually means around 500 to 600 ng/dl. The concentration of testosterone in the blood actually goes up quite quickly, within a few doses. I normally measure it after 2 weeks, even although symptoms may not alter for a month or two.