Dhea - Faslodex (Fulvestrant) Interaction
Herbal: Dhea
Also Known As: 3b-Hydroxy-Androst-5-Ene-17-One, 3BetaHydroxy-Androst-5-Ene-17-One, Androstenolone, Déhydroépiandrostérone, DHEA-S, GL701, Prasterone
Drug: Fulvestrant
Brand names:
Faslodex
Medical Content Editor Dr. Brian Staiger, PharmD
Last updated
May 25, 2025
Interaction Details
Fulvestrant is classified as belonging to the following category: Fulvestrant (Faslodex)
Theoretically, DHEA might interfere with the anti-estrogen effects of fulvestrant.
DHEA is a potent estrogen agonist. Some research shows that it can overcome the estrogen receptor antagonist action of fulvestrant in estrogen-receptor positive cancer cells.
Interaction Rating
Likelihood of Occurrence
PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists
References
- Calhoun KE, Pommier RF, Muller P, et al. Dehydroepiandrosterone sulfate causes proliferation of estrogen receptor-positive breast cancer cells despite treatment with fulvestrant. Arch Surg 2003;138:879-83..
- Morris KT, Toth-Fejel S, Schmidt J, et al. High dehydroepiandrosterone-sulfate predicts breast cancer progression during new aromatase inhibitor therapy and stimulates breast cancer cell growth in tissue culture: a renewed role for adrenalectomy. Surgery
Dhea Overview
Dehydroepiandrosterone (DHEA) is a natural (i.e., endogenous) hormone produced by the adrenal gland and is among the most abundant steroid hormones in the human body. It is a precursor to the hormones testosterone and estrogen, and it is thought to have various effects on the body. DHEA levels naturally decline with age. It is a popular over the counter supplement that is purported to have a variety of health benefits, including increasing muscle mass, improving cognitive function, improving mood and reducing the risk of heart disease and diabetes. The scientific evidence supporting the use of DHEA for these purposes is limited and mixed. Additionally, it could potentially interact with several different medications so if you are considering taking DHEA supplements, it is important to speak with a healthcare professional.
DHEA should not be confused with other supplements containing the letters 'DHEA'. 7-alpha-hydroxy-DHEA, 7-beta-hydroxy-DHEA, and 7-keto-DHEA, all contain DHEA as the parent compound with additional structures attached.
Fulvestrant Overview
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Fulvestrant injection is used alone or in combination with ribociclib (Kisqali®) to treat a certain type of hormone receptor positive, advanced breast cancer (breast cancer that depends on hormones such as estrogen to grow) or breast cancer has spread to other parts of the body in women who have experienced menopause (change of life; end of monthly menstrual periods) and have not previously been treated with an anti-estrogen medication such as tamoxifen (Nolvadex). Fulvestrant injection is also used alone or in combination with ribociclib (Kisqali®) to treat hormone receptor positive, advanced breast cancer or breast cancer that has spread to other parts of the body in women who have experienced menopause and whose breast cancer has worsened after they were treated with an anti-estrogen medication such as tamoxifen. Fulvestrant injection is also used in combination with palbociclib (Ibrance®) or abemaciclib (Verzenio®) to treat hormone receptor positive, advanced breast cancer in women whose breast cancer has spread to other parts of the body and has worsened after they were treated with anti-estrogen medication such as tamoxifen. Fulvestrant is in a class of medications called estrogen receptor antagonists. It works by blocking the action of estrogen on cancer cells. This can slow or stop the growth of some breast tumors that need estrogen to grow.
Dhea - More Interactions
Dhea interacts with 754 drugs
Interaction Rating Key
These severity listings are for informational use only. Never start, stop or otherwise change your therapy before speaking with your provider.
| Major | The combined use of these agents is strongly discouraged as serious side effects or other negative outcomes could occur. |
| Moderate | Use cautiously under the care of a healthcare professional or avoid this combination. A significant interaction or negative outcome could occur. |
| Minor | Be aware that there is a chance of an interaction. Watch for warning signs of a potential interaction. |
| Unknown | No interactions have been reported or no interaction data is currently available. |
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Parts of this content are provided by the Therapeutic Research Center, LLC.
DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.
© 2021 Therapeutic Research Center, LLC
Drug descriptions are provided by MedlinePlus.
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Dr. Brian Staiger, PharmD
In addition to being a clinical pharmacist specializing in pharmacotherapy, Dr. Brian Staiger is a registered herbalist through the American Herbalist Guild. He has combined his passion for pharmacy practice with the study of medical ethnobotany to improve patient care. Feel free to reach out about any of your herbal or medication questions!
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