Eurycoma Longifolia - Faslodex (Fulvestrant) Interaction
Herbal: Eurycoma Longifolia
Also Known As: Akar Pasak Bumi, Ali's Umbrella, Ali's Walking Stick, Bedara Pahit, Canne d'Ali, Cay ba binh, Eurycoma, Eurycoma Longifolia Jack, Ian-don, Jelaih, Long Jack, Longjack, Malaysian Ginseng, Pasak Bumi, Payung Ali, Pokok Jelas, Pokok Syurga, Setunjang Bumi, Tho Nan, Tongkat Ali
Drug: Fulvestrant
Brand names:
Faslodex
Medical Content Editor Dr. Brian Staiger, PharmD
Last updated
May 11, 2025
Interaction Details
There were no interactions found between Fulvestrant and Eurycoma Longifolia. This does not mean the potential for an interaction does not exist, however. There is often a lack of studies and data surrounding traditional medicine, especially concerning drug interactions, so it is important to always consult your provider before making any changes to your medication regimen.
Pharmacist Analysis
Although there is no known interaction in this case, Eurycoma longifolia, most commonly known as Tongkat Ali, does have some potential interactions that are important to be aware of.
For example, it may interact with the following:
- CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES
- CYTOCHROME P450 2C19 (CYP2C19) SUBSTRATES
- CYTOCHROME P450 2A6 (CYP2A6) SUBSTRATES
- Propranolol
- Testosterone
Tongkat Ali has been reported to inhibit certain metabolizing enzymes in the liver (the ones mentioned above) and therefore, may increase the levels of substances metabolized by those enzymes. This could potentially affect the way these substances work or how long they stay in your system.
In regard to propranolol, some studies show that Tongkat Ali decreases how well propranolol is absorbed in the gut and could reduce its effects. It is not known if separating administration will prevent this interaction/
Lastly, testosterone, Tongkat Ali may theoretically further increase levels of testosterone, a hormone responsible for various functions in the body. You should be cautious combining the two.
- Dr. Brian Staiger, PharmDEurycoma Longifolia Overview
Eurycoma longifolia, also known as tongkat ali or "Malaysian ginseng," is a plant native to Southeast Asia. It is a member of the Simaroubaceae family and is known for its small, yellow flowers and elongated, slender leaves.
It has a long history of use in traditional medicine and is thought to have anti-inflammatory and pain-relieving effects.
Eurycoma longifolia is also purported to have a number of other medicinal properties, including the ability to improve immune function, reduce the risk of heart disease, and lower cholesterol levels.
Additionally, Eurycoma longifolia is commonly used as a natural treatment for male infertility and as a natural performance-enhancing supplement as it may have a mild androgenic effect. When used for male enhancement, it is most often marketed under other common names for the plant (e.g., tongkat ali, longjack).
Fulvestrant Overview
-
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.
Eurycoma Longifolia - More Interactions
Eurycoma Longifolia interacts with 247 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. |
Return to the main supplement interaction checker page
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.
Ask A Pharmacist About Your Herbal Questions!
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!
Ask A Pharmacist