This is from The Mayo Clinic;
"DHEA (dehydroepiandrosterone) is an endogenous hormone (made in the human body), and secreted by the adrenal gland. DHEA serves as precursor to male and female sex hormones (androgens and estrogens). DHEA levels in the body begin to decrease after age 30, and are reported to be low in some people with anorexia, end-stage kidney disease, type 2 diabetes (non-insulin dependent diabetes), AIDS, adrenal insufficiency, and in the critically ill. DHEA levels may also be depleted by a number of drugs, including insulin, corticosteroids, opiates, and danazol.
There is sufficient evidence supporting the use of DHEA in the treatment of adrenal insufficiency, depression, induction of labor, and systemic lupus erythematosus.
No studies on the long-term effects of DHEA have been conducted. DHEA can cause higher than normal levels of androgens and estrogens in the body, and may increase the risk of prostate, breast, ovarian, and other hormone-sensitive cancers. Therefore, it is not recommended for regular use without supervision by a licensed health professional."
Side effects & Cautions; (From MedlinePlus)
"DHEA is not recommended for people under 40 years of age, unless DHEA levels are known to be low (less than 130 mg/dL in women and less than 180 mg/dL in men). People taking DHEA should have their blood levels monitored every 6 months.
Side effects may include fatigue, nasal congestion, headache, acne, or rapid/irregular heartbeats. In women, the most common side effects are abnormal menses, emotional changes, headache, and insomnia. Individuals with a history of abnormal heart rhythms, blood clots or hypercoagulability, and those with a history of liver disease, should avoid DHEA supplements.
Because DHEA is a hormone related to other male and female hormones, there may be side effects related to its hormonal activities. For example, masculinization may occur in women, including acne, greasy skin, facial hair, hair loss, increased sweating, weight gain around the waist, or a deeper voice. Likewise, men may develop more prominent breasts (gynecomastia), breast tenderness, increased blood pressure, testicular wasting, or increased aggressiveness. Other hormonal-related side effects may include increased blood sugar levels, insulin resistance, altered cholesterol levels, altered thyroid hormone levels, and altered adrenal function. Caution is advised in patients with diabetes or hyperglycemia, high cholesterol, thyroid disorders, or other endocrine (hormonal) abnormalities. Serum glucose, cholesterol and thyroid levels may need to be monitored by a healthcare professional, and medication adjustments may be necessary.
High DHEA levels have been correlated with Cushing’s syndrome, which may be caused by excessive supplementation.
DHEA may interfere with the way the body processes certain drugs using the liver’s “cytochrome P450” enzyme system. As a result, the levels of these drugs may be increased in the blood, and may cause increased effects or potentially serious adverse reactions. Central nervous system agents, including carbamazepine and phenytoin, induce the P450 enzymes that metabolize DHEA and DHEA-S and therefore can decrease circulating concentrations of these hormones.
DHEA may increase blood sugar levels. Caution is advised when using medications that may also lower blood sugar such as metformin (Glucophage®). A qualified healthcare professional should closely monitor patients taking drugs for diabetes by mouth or insulin. Medication adjustments may be necessary.
DHEA may increase the risk of blood clotting. Patients who take anticoagulants (blood thinners) or antiplatelet drugs (such as aspirin) to prevent blood clots should discuss the use of DHEA with a healthcare professional. Examples of blood thinning drugs include warfarin (Coumadin®), heparin, and clopidogrel (Plavix®). The risk of blood clots is also increased by smoking or by taking other hormones (such as oral contraceptives or hormone replacement therapy), and these should not be combined with DHEA unless under medical supervision.
DHEA may alter heart rates or rhythm, and should be used cautiously with heart medications or drugs that may also affect heart rhythm. Alcohol may increase the effects of DHEA."