Fig 6. Changes in DHEA, DHEA-S, testosterone, dihydrotestosterone, and androstenedione after 400 mg oral DHEA in a 72 year-old man. DHEA-S, mcg/dl. All others, ng/dl. 14
(click on thumbnail for full sized image) On the other hand, when pharmacologic doses of DHEA are administered (., doses that are far in excess of those required to restore levels to those of healthy young adults), testosterone and DHT levels do increase significantly. For example, in one elderly man, to whom 400 mg of DHEA was administered, significant and rapid rises were noted in DHEA, DHEA-S , testosterone and DHT (Figure 6). 14
DHEA is transformed into DHEA-S by sulfation at the C3β position via the sulfotransferase enzymes SULT2A1 and to a lesser extent SULT1E1 .    This occurs naturally in the adrenal cortex and during first-pass metabolism in the liver and intestines when exogenous DHEA is administered orally. [ citation needed ] Levels of DHEA-S in circulation are approximately 250 to 300 times those of DHEA.  DHEA-S in turn can be converted back into DHEA in peripheral tissues via steroid sulfatase (STS).  
One alternative to straight testosterone replacement is to boost the levels of the hormones that stimulate testosterone production instead. DHEA , for example, is a "parent hormone" made in the adrenal gland and testes, which changes into testosterone in men and estrogen in women. One solution to low testosterone is DHEA supplements , which naturally raise the body's testosterone levels. The advantage is that the body never slows its own efforts to make the hormone the way it does with testosterone replacement, and it doesn't require some of the difficult, often messy delivery systems (transdermal gels or pellets) that testosterone does. According to clinical integrative pharmacist Scott Berliner, the possibility of abnormally low levels of DHEA is worth investigating when someone is suffering from low T, something traditional physicians may overlook. “If a 45-year-old man comes in with a level of 200, they give you testosterone. End of story. In the integrative model, we're always looking for the cause of things." And often the cause is a deficiency in DHEA. According to the National Institutes of Health, raising the body's level of DHEA can increase sexual function and may build muscle mass. There's a reason it's banned by the NCAA. Taking the supplemental hormone in high doses and for long periods of time is not recommended, as that can exacerbate side effects.