Androgens in Health and Disease.pdf - E Library

Chapter 22/Androgens in Primary Care 435
evidence of corticosteroid excess, and no complaints of headache or visual disturbances
do not need to pituitary imaging. All other men with secondary hypogonadism should
have a pituitary CT or MRI to exclude a macroadenoma. Men who are seeking fertility
should be referred to an endocrinologist or reproductive specialist.
The benefits of androgen-replacement therapy outweigh the hazards for most
hypogonadal men. Men with very low total testosterone levels (24 mo for maximal benefit. Therefore, if a patient and physician elect to
embark on a trial of testosterone therapy, 6 mo is generally an adequate trial. Most
patients who do not experience a benefit will discontinue androgen therapy on their own
after 6 mo.
The choice of androgen replacement depends on cost, convenience, and amount of
androgen administration clinically necessary. Intramuscular testosterone is the least
expensive therapy, but it requires biweekly intramuscular injections. Transdermal
patches and gel offer a less invasive route of administration, but they must be applied
daily and are much more costly than intramuscular testosterone therapy. Testosterone
gel is more likely to restore serum testosterone levels than any of the patch systems, and
the gel formulation is less likely to cause skin irritation. However, testosterone gel is very
expensive and carries a risk of vicarious transfer of testosterone to household contacts
and sexual partners.
There is a great deal of research and development occurring in the area of androgen
effects in men. As we learn more about the effects and develop new therapies, we shall be
better prepared to identify which men will benefit from exogenous androgen administration,
and we will have the ability to tailor the androgen therapy for their individual needs.
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