Pharmacokinetics

As a nutritional supplement, DHEA is most commonly administered by the oral route. Many DHEA products available as nutritional supplements contain varied amounts of DHEA and do not appear to be manufactured according to good manufacturing processes (GMP). Using HPLC techniques, one study found that only 7 out of the 16 assayed products contained DHEA within a 10% variation of the labeled content.(7) Some products contained no detectable DHEA.(7)

The literature is lacking in pharmacokinetic studies using serial serum sampling of DHEA after supplementation. In the body, DHEA and DHEAS are widely distributed, converted to the sex hormones in peripheral tissues, and appear to cross the blood-brain barrier. The serum pharmacokinetic parameters and metabolism of DHEA and DHEAS following administration may vary among persons of different sex and age groups and the dose or route of administration. Quantification of DHEA to aide in detection of abuse by athletes may soon be accomplished. Gas chromatography-mass spectrometry (GC-MS) can evidently detect DHEA metabolites in the urine within 8 hours of a single oral dose of 50 mg. Within 24 hours, 50—75% of an oral DHEA dose is recovered as glucuronide and sulfate conjugates, androsterone, and etiocholanone in the urine.

Route-Specific Pharmacokinetics:

Oral Route: Micronization appears to enhance oral absorption and may influence the metabolic conversion of DHEA to the various sex hormones in men and women. After oral dosing, elevations in serum concentrations of DHEA and DHEAS, above endogenous levels, persist for 12 hours.