If you buy DHEA without a prescription, you can generally find it in 10, 25, and 50 mg capsules.
One of the practical problems of taking DHEA orally is that the blood supply from the stomach and intestines goes through the liver before making its way to the rest of the body. The liver is the chemical factory of the body and it makes good sense for it to have "first crack" at the blood supply from the digestive system. Physicians call this the "first-pass effect."
One of the liver's functions is to metabolize sterols and steroids. Cholesterol is a common dietary sterol and the liver bundles it into lipoproteins (fatty globules) for distribution to body tissues. If there's not enough cholesterol in the foods we eat, the liver makes more of it to make up the difference. The liver also metabolizes DHEA. Because of this, DHEA pills that you swallow will first be metabolized by the liver and the amount that reaches the general circulation will likely be less than the ingested dose. The factors that influence absorption from the intestines and metabolism by the liver vary significantly with age and health condition. Testing (before and after DHEAS levels) may be the only way to know for sure how much is making it into the bloodstream.
One of the ways that pharmacists minimize liver metabolism of steroids is to use "micronized" preparations. Micronization is a process that creates tiny particles that can be absorbed from the intestines into the lymphatic system and somewhat bypass the liver. Although micronized DHEA is now available on a limited basis, I have seen only limited data supporting its proposed enhanced bioavailability.
Another possible route to minimizing liver metabolism of DHEA is by sublingual administration. Sublingual refers to under-the-tongue use which allows a significant amount of DHEA to be absorbed into the tiny capillaries of the mouth whose blood supply passes into the general circulation before going to the liver. Sublingual preparations of many vitamins, drugs and herbal extracts are common. Even melatonin comes sublingually. However, I have not seen any research to indicate whether the sublingual approach to DHEA supplementation is preferable to the oral route.
Ron von Vollenhoven, M.D., Ph.D., Division of Immunology and Rheumatology, Stanford University Medical Center, CA.
It's been difficult to predict serum levels of DHEAS based on dosages from oral administration since the absorption rates are often variable.
John Buster, M.D., Director, Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, Texas, has been studying, along with Peter Casson, M.D., the bioavailability of DHEA.
Our studies indicate that micronized DHEA gets absorbed more easily from the intestinal system by being absorbed through the lymphatic system, partially bypassing the liver. This form of DHEA also does not seem to be converted to testosterone as much thus possibly reducing negative androgenic effects on the prostate gland or lipids (Casson and Buster, 1995).
I am not aware of any data comparing saliva tests versus blood tests. As to the ideal time of dosing, again, I'm not aware of any data to indicate what time of day is best.
Our knowledge with DHEA is where estrogen was about two or three decades ago.
What's the best dosage to start with?
There is a wide range of opinions on the ideal starting dosage. I am generally conservative in my approach and prefer most medicines to be started at a low dose. For instance, my feeling about melatonin is that 0.3 mg is a safe dose for the first night. This dose is low compared to the fact that most pills in the vitamin stores come in 3 mg. If this low dose is not effective, then it can be increased the following night.