Is It Time to Add Testosterone?
By Louanne Cole Weston, PhD

Before you begin medical treatment, there are some additional things to consider and do.

You might indeed be a good candidate for testosterone supplementation. Before you begin medical treatment, however, here are some additional things to consider and do.

You may have had a significant drop in your testosterone, but before you conclude that, you should know that laboratories vary in how they perform testosterone tests. To be sure of the result, have all your testosterone tests done at the same location at roughly the same time of day. The apparent drop in your total testosterone could be due to lab error, testing at different labs, or circadian cycling. (Hormones fluctuate throughout the day, so testing at about the same time is best.)

You could get another test of your total testosterone, but according to Dr. Henry Ritter, a urologist from Atherton, Calif., the more useful number to know is the "free testosterone" (or bioavailable testosterone). The "total testosterone" reflects free and bound testosterone. Bound testosterone is not available to boost libido because it is linked to proteins, such as albumin and sex hormone binding globulin, according to Dr. John E. Gould, associate clinical professor of urology at the University of California at Davis. Gould also recommends getting the free testosterone number.

Different labs measure free testosterone differently. But ranges they consider "normal" generally fall between 260 nanograms/deciliter to 1,000 ng/dL. (2.6 nanograms/milliliter to 10 ng/mL). Since physicians and laboratories are only recently beginning to recognize the importance of testing free testosterone, you may have to lobby to get the test. If you are unable to get that reading and are forced to stick with total testosterone, learn the range of normal for your lab. Normal ranges for men usually are between 250 ng/dL to 1,200 ng/dL of blood (2.5 ng/mL to 12 ng/mL).

Keep in mind that these ranges are created by testing many men without much attention to their relative level of sexual function. Men whose testosterone level is in the lowest 20% of the normal ranges above may not feel much sex drive at all. In my clinical experience as a sex therapist, men with total testosterone readings in the low 400s tend not to have much sexual drive even if they are in fulfilling relationships. Ritter says that even some men in the 600s do not feel that much drive when other things are equal, and he prefers to see numbers in the 700s. Throwing things into further confusion, says Gould, is the fact that sometimes free testosterone will be low when the total testosterone is high and vice versa.

One of the problems with all this measuring, Ritter says, is that very few men have baseline measurements of their testosterone (free or total) during the time their sex drive was normal. So there is no way to know whether they have experienced a relative decrease. Also, there are probably men who would test low but who would not complain at all about the strength of their sexual drive. Clearly, determining the best testosterone level for you is not an exact science since a key component involves personal expectations about sexuality, a very complex matter.

According to Gould and Ritter, testosterone does not affect sexual function, only sexual drive. (And it is certainly not the only component of sexual drive.) So look for other explanations and solutions if erection difficulties or problems with the timing of orgasm occur (see Sexual Dysfunction).

If you do find a low level of free testosterone in two separate readings from the same laboratory, Ritter and Gould recommend getting several other lab tests to determine if you're a good candidate for testosterone supplements:

-baseline liver function, or LFT
-complete blood count, or CBC
-prostate-specific antigen, or PSA
-prolactin level
-luteinizing hormone level, or LH
-digital rectal exam
-follicle stimulating hormone test, or FSH (optional)

Taking testosterone is dangerous only if you have certain medical conditions. For starters, it's important to check your liver function before, and at regular intervals during, a testosterone-supplementation program. If there is a negative impact to the liver, it can be reversed by discontinuing the testosterone, says Gould.

According to Ritter, prostate cancer either in your own history or your immediate family history rules out taking testosterone. An enlarged prostate that isn't cancerous, however, is not a deal-breaker -- a PSA test will let you know where you stand. The other tests help rule out other hormone problems: An abnormal LH test or prolactin level, says Gould, will alert your physician to check your pituitary for a malfunction or tumor. FSH testing can help determine if your sperm production is low.

Other potential risks: So far, no study provides solid evidence that taking testosterone will cause hypertension or a substantial increase in cholesterol levels. It may cause a slight rise in blood pressure or "bad" cholesterol (low-density lipoprotein), but generally not to levels that are significant or irreversible.

Currently, testosterone can be administered by injection, pill, or skin patch. Most physicians favor either the injection or patch because the pill has more potential for negative medical consequences. Ritter states that about 10% of men who use pills develop a condition known as chemical hepatitis and must discontinue. Gould says that pills are generally "just hard on the liver."

With injections there are infrequent liver problems and they are generally reversible. The two negatives: the annoyance of getting a shot every two weeks to three weeks, and the "spike effect," which gives a man a sudden boost of testosterone that usually wears off by the time of the next injection.

The skin patch also causes liver problems only infrequently and has the added advantage of eliminating the spike effect because the same amount of testosterone is absorbed through the skin each day as a new patch is applied. The patch approach is slightly more expensive than injections, but involves no needles.

At 50, you would be very wise to have an annual prostate check anyway, even if you do not decide to supplement your testosterone. And just as importantly, let your wife know about these options and talk it over with her. If she's noticed your lowered sexual drive, she's probably been wondering about it as well.