Herbs & Supplements

What interactions should I watch for?

Prescription Drugs

Some research has found an association between psychotic disorders and high levels of natural DHEA. Whether supplemental DHEA may cause or worsen psychoses is not known. In theory, though, taking DHEA may interfere with drugs that are used to treat psychosis. Some antipsychotic drugs are:

• chlorpromazine (Thorazine)
• fluphenazine (Prolixin)
• prochlorperazine (Compazine)
• Risperdal
• Seroquel
• Zyprexa

Corticosteroid drugs are used for a wide range of inflammatory conditions including arthritis, asthma, cancer, eye conditions, and skin infections. They have also been shown to reduce the amount of DHEA made by the body. When supplemental DHEA is taken at the same time as corticosteroids, effects of both the drug and the supplement may be unpredictable. It is advised not to take DHEA and corticosteroids at the same time. Commonly prescribed corticosteroids include:

• beclomethasone (Beconase, Vancenase)
• dexamethasone
• hydrocortisone
• methylprednisolone (Medrol)
• prednisolone
• prednisone
• triamcinolone (Azmacort, Nasacort)

Although the reason is not clearly defined, insulin and DHEA seem to interfere. Some scientific evidence supports the theory that insulin decreases DHEA made by the body, while other studies appear to show that high doses of DHEA increase insulin resistance (the body's inability to use insulin normally). In general, taking DHEA while using insulin is not recommended. Individuals who have diabetes but who do not use insulin to treat their diabetes should talk to their doctors before beginning to use DHEA.

In one study, blood levels of triazolam (Halcion) increased when DHEA was taken at the same time. Triazolam is used to treat insomnia. Increased blood levels of triazolam may result in excessive drowsiness or dizziness. Drugs similar to triazolam include alprazolam and diazepam. Individuals who are taking any prescription drug that promotes sleep or relaxation should talk to doctor before starting to take DHEA at the same time.

DHEA is changed in the body to estrogen and androgen, hormones responsible for sexual characteristics. In theory, taking DHEA at the same time as these hormones could cause high levels of the hormones in the blood.

• If DHEA is taken with estrogen or oral contraceptives, estrogen levels may become too high. Symptoms of high estrogen levels include:
  • Bloating
  • Breast tenderness
  • High blood pressure
  • Upset stomach
• If DHEA is taken at the same time as testosterone, testosterone levels may become too high and liver damage may occur. Symptoms of high testosterone include:
  • Breast enlargement
  • Changes in sex drive
  • Prostate enlargement
  • Swelling

In a few small studies, the effects of aromatase inhibitors (Arimidex, Aromasin, and Femara), Faslodex, and tamoxifen--drugs used to treat breast cancer--were lessened among study participants whose blood levels of DHEA-S were higher than 89 micrograms per deciliter.

DHEA is broken down by certain enzymes in the liver, therefore it may interfere with prescription drugs that are processed by the same enzymes. Some of these drugs are:

• Allergy drugs such as fexofenadine (Allegra)
• Antifungal drugs such as itraconazole (Sporanox)and ketoconazole (Nizoral)
• Cancer drugs such as etoposide (VePesid), paclitaxel (Taxol), vinblastine, or vincristine
• Drugs for high cholesterol such as lovastatin
• Oral contraceptives

Some research in animals suggests that the mood-stabilizing drug lithium may reduce the levels of DHEA and DHEA-S in the brain. No serious problems are believed to result, but doses of DHEA may not be as effective as expected if lithium is taken at the same time.

Herbal Products

Some evidence shows that eating or taking large amounts of soy can decrease the effects of DHEA. While no serious consequences have been reported, the intended effects of DHEA may be lessened.

Foods

Individuals who consume large amounts of soy-based foods should be aware that the results of DHEA may be reduced.

Some interactions between herbal products and medications can be more severe than others. The best way for you to avoid harmful interactions is to tell your doctor and/or pharmacist what medications you are currently taking, including any over-the-counter products, vitamins, and herbals. For specific information on how DHEA interacts with drugs, other herbals, and foods and the severity of those interactions, please use our Drug Interactions Checker to check for possible interactions.