Patients should avoid if allergic to DHEA products.

Few side effects are reported when DHEA supplements are taken by mouth in recommended doses. 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.

In theory, DHEA may increase the risk of developing prostate, breast, or ovarian cancer. DHEA may contribute to tamoxifen resistance in breast cancer. Other side effects may include insomnia, agitation, delusions, mania, nervousness, irritability, or psychosis.

High DHEA levels have been correlated with Cushing's syndrome, which may be caused by excessive supplementation.

DHEA is not recommended during pregnancy or breastfeeding. Because DHEA is a hormone, it may be unsafe to the fetus or nursing infants.

DHEA is available as capsules, tablets and injections. Commonly used doses range from 25-200 milligrams daily. Higher doses of 200-500 milligrams per day have been studied for depression in HIV/AIDS. Daily use of DHEA has been studied up to one year in the available scientific studies.

Topical (on the skin) and intravenous injections (into the veins) have also been studied, but safety and effectiveness has not been proven. A 5-10% cream containing DHEA has been used up to four weeks.

The dosing and safety of DHEA are not well studied in children. In theory, DHEA could interfere with normal hormone balance and growth in children.

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. Patients using any medications should check the package insert and speak with a qualified healthcare professional, including a pharmacist, about possible interactions.

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.

Although it is not widely studied, there are some reports that drugs such as canrenoate, anastrozole (Arimidex®), growth hormones, methylphenidale, amlodipine, nicardipine and other calcium channel blockers like diltiazem (Cardizem®) and alprazolam (Xanax®) may increase DHEA levels in the body, which could lead to increased side effects when taken with DHEA supplements. In theory, increased hormone levels may occur if DHEA is used with estrogen or androgen hormonal therapies. DHEA may interact with psychiatric drugs such as clozapine (Clozaril®).

DHEA may interact with GABA-receptor drugs used for seizures or pain. DHEA may decrease the effectiveness of methadone. DHEA may add to the effects of clofibrate or contribute to tamoxifen resistance in breast cancer.

DHEA use has been suggested to result in a decreased rate of developing protective antibody titer after influenza vaccination.

Drugs that reduce the normal levels of DHEA produced by the body include dopamine, insulin, corticosteroids such as dexamethasone, drugs used to treat endometriosis such as danazol, opiate painkillers, antipsychotics, and estrogen-containing drugs. Metopirone, alprazolam and benfluorex may increase blood DHEA levels. Many other interactions are possible; check with a qualified healthcare professional including a pharmacist, for a thorough list.

Based on laboratory and animal studies, DHEA may interfere with the way the body processes certain herbs or supplements using the liver's "cytochrome P450" enzyme system. As a result, the levels of other herbs or supplements may become too high in the blood. It may also alter the effects that other herbs or supplements possibly have on the P450 system.

DHEA may raise blood sugar levels or cause insulin resistance, and may add to the effects of herbs/supplements that may also increase blood sugar levels, such as arginine, cocoa, ephedra (when combined with caffeine), or melatonin. DHEA may work against the effects of herbs/supplements that may decrease blood sugar levels, such as Aloe vera, American ginseng and bilberry. Serum glucose levels should be monitored closely by a qualified health care professional while using DHEA. Dosing adjustments may be necessary.

In theory, DHEA may increase the risk of blood clotting, and may add to the effects of herbs/supplements that may also increase the risk of clotting, such as coenzyme Q10 or Panax ginseng. DHEA may work against the effects of herbs/supplements that may "thin" the blood and reduce the risk of clotting, such as Ginkgo biloba, garlic, and saw palmetto.

It is not known what effects occur when DHEA is used with herbs that are believed to have hormonal effects in the body. Examples of agents with possible estrogen-like (phytoestrogenic) effects in the body include alfalfa, black cohosh, and bloodroot.

DHEA may alter heart rates or rhythms. Caution is advised in patients taking herbs/supplements that may alter heart function or that include cardiac glycosides. Examples include adonis, balloon cotton, and foxglove/digitalis.

Chromium picolinate may increase blood DHEA levels. Carnitine and DHEA may have additive effects. Based on animal research, DHEA may increase melatonin secretion and prevent breakdown of vitamin E in the body.

Although it is not widely studied, there are some reports that DHEA may also interact with fiber, flavanoids, polyunsaturated fatty acids, probiotics, soy protein and yam. Caution is advised.