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Chickweed |
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Devils Claw |
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Dhea And Dhea-s Herb - Dosage and Useful Properties
Taxonomic Class
Dioscoreaceae
Common Trade Names
Multi-ingredient preparations: Born Again's DHEA Eyelift Serum, DHEA Men's Formula, DHEA with Antioxidants 25 mg, DHEA with Bioperine 50 mg
Common Forms
Capsules: 5 mg, 25 mg, 50 mg
Cream: 4 oz (with other vitamins and herbs)
Tablets (timed-release): 15 mg
Source
Steroid precursors found in members of the yam family have been used to produce dehydroepiandrosterone (DHEA). Most commercially available DHEA is produced in Europe and China.
Aside from its occurrence in certain plants, the neurosteroid hormone DHEA (S-androsten-3beta-ol-17-one) and DHEA-S are secreted exclusively by the zona reticularis of the adrenal gland (in response to adrenocorticotropin) in women; small quantities are also secreted from the testes. DHEA-S, the most abundant circulating steroid hormone of the two, is the hydrosteroid sulfatase metabolite of DHEA.
DHEA concentrations are highest in the brain, with lesser concentrations in the plasma, spleen, kidneys, and liver (in descending order).
Chemical Components
DHEA (5-androsten-3beta-ol-17-one) and DHEA-S have structural origins that result from a cholesterol nucleus. Pregnenolone is the immediate precursor to DHEA, which is converted from pregnenolone by 17,20desmolase. DHEA serves as a substrate in which to synthesize half the endogenous androgens in men and most of the estrogens in women. DHEA has a shorter half-life (1 to 3 hours versus 10 to 20 hours, respectively) and is less highly bound to albumin than DHEA-S.
Actions
A comprehensive review by Kroboth and colleagues provides more detail on the complex effects, clinical trials , and metabolic pathway of DHEA and DHEA-S.
In humans, serum levels of DHEA peak at age 20 and again at age 40 and then decline dramatically to about 20% to 30% of maximum by age 70 to 80. Documentation of this age-related decline in DHEA levels has led to suggestions that exogenous DHEA supplementation could result in a "fountain of youth" effect. Some preliminary evidence suggests that DHEA-S may be a marker for Alzheimer's disease and erectile dysfunction . Several physiologic effects have been ascribed to DHEA, including its conversion into androgens and estrogens and its ability to raise serum levels of insulin-like growth factor 1, a mediator of human growth hormone. The degree of androgenic versus estrogenic effect of DHEA appears to depend on the patient's hormonal milieu. DHEA has been shown to reduce luteinizing hormone through direct pituitary inhibition . In men, DHEA has also been reported to increase levels of several immune cell types. Several aspects of disease have been shown to influence DHEA and DHEA-S serum levels, including age, gender, serious illness, burns, and acute exercise .
Reported Uses
Numerous claims for health benefits with regular DHEA use have been touted in the scientific and lay press. They include immune system enhancement; antidiabetogenic, antineoplastic, and anti atherosclerotic effects; osteoporosis prevention; treatment for certain autoimmune conditions; and a general antiaging effect. Seemingly positive benefits in animal studies have generally met with mixed results or less when similar studies have been conducted in humans.
At least two trials have suggested that DHEA supplementation promotes a greater sense of well-being . Questions have been raised about study design in these trials. A Cochrane Database Review determined that evidence supporting this kind of effect is limited. The review also pointed out that essentially no evidence exists supporting DHEA supplementation as a nootropic (enhances cognitive function) agent .
Two placebo-controlled trials argue against any potential anabolic effect from DHEA supplementation.
Small trials have been conducted evaluating DHEA supplementation in light of its effects on sleep, diet and body composition, SLE, HIV infection , menopausal symptoms and anorexia nervosa . All work in these areas is considered preliminary .
Dosage
Various doses have been used in human studies. Doses have ranged from 50 to 1,600 mg daily. It has been suggested but not agreed on that serum levels of DHEA-S should be checked periodically during exogenous replacement and the dose adjusted to youthlike levels
(3,600 mg/ml for men and 3,000 mg/ml for women). DHEA has been administered by various routes, including LV., subcutaneous, transdermal, and vaginal.
Adverse reactions
CNS: aggressiveness, fatigue, headache, insomnia, irritability.
EENT: nasal congestion.
GI: elevated liver function test results.
Hematologic: slightly decreased hemoglobin level and RBC count.
Skin: hirsutism.
Other: gynecomastia.
Interactions
This list presents information from reports of drugs and their potential effect on endogenous DHEA or DHEA-S serum levels; however, the absolute effect on these levels mayor may not be similar when exogenous DHEA is ingested in combination with the interacting drug.
Alprazolam: May increase endogenous serum levels of DHEA. DHEA-S concentrations were not changed . Evaluate the need for combination therapy.
Calcium channel blockers: Increases endogenous serum DHEA and DHEA-S levels in obese, hypertensive men . Monitor the patient and adjust dose as needed.
Carbamazepine, dexamethasone: Decreases endogenous serum levels of DHEA-S . Monitor the patient and adjust dose as needed.
Insulin (exogenous): Decreases serum levels of DHEA and DHEA-S in men . Monitor the patient and adjust dose as needed.
Insulin-sensitizing drugs (metformin, other oral hypoglycemics): May increase serum DHEA and DHEA-S levels . Monitor the patient and adjust dose as needed.
Although not documented, DHEA may interact with other exogenous androgen or estrogen hormone therapies. Monitor the patient taking both of these agents.
Contraindications And Precautions
DHEA is contraindicated in patients with benign prostatic hyperplasia, estrogen-responsive tumors (such as those of the breast and uterus), or prostate cancer because of DHEA's potential for promoting growth of these tumors. Avoid using DHEA in pregnant or breast-feeding patients; effects are unknown.
Special Considerations
Alert Patients older than age 40 should be aggressively screened for hormonally sensitive cancers before taking DHEA.
Monitor the patient for excessive hair growth.
Instruct the patient to report mood or behavioral changes.
Advise women to avoid using DHEA during pregnancy or when breast - feeding.
Monitor the male patient for breast enlargement.
Commentary
Many claims for DHEA use are based on in vitro or animal studies; moreover, nonprimate mammals do not produce significant amounts of endogenous DHEA, so using them in clinical studies may be erroneous. Although declining DHEA levels in humans may be assumed to act as a marker for aging and degenerative diseases, inconclusive evidence exists that exogenous DHEA replacement will prevent or be therapeutic for such conditions. Long-term safety data for DHEA use in humans are also lacking. Larger, more comprehensive trials are needed to determine a role for this agent.
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