Interaction Details

There were no interactions found between Conjugated Estrogens and Evening Primrose. 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.


Still looking for more information about combining Conjugated Estrogens and Evening Primrose? Ask Dr. Brian Staiger about it by contacting him directly.

Evening Primrose Overview

Evening Primrose Evening primrose (Oenothera biennis) is a plant native to North and Central America and a member of the Onagraceae family. It is an annual plant that has bright yellow flowers that bloom in the evening (hence the name). The plant produces seeds that are rich in a fatty acid called gamma-linolenic acid (GLA). Evening primrose oil is a dietary supplement that is derived from the seeds of the evening primrose plant. It is rich in GLA (gamma-linolenic acid), an omega-6 fatty acid, and is sometimes taken to improve the health of the skin, reduce inflammation, and reduce the symptoms of premenstrual syndrome (PMS). It has also been used historically for alcohol use disorder. Dietary supplements containing evening primrose oil generally are standardized by their gamma-linolenic acid (GLA) and linoleic acid (LA) content.
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Conjugated Estrogens Overview

  • The estradiol cypionate and estradiol valerate forms of estrogen injection are used to treat hot flushes (hot flashes; sudden strong feelings of heat and sweating) and/or vaginal dryness, itching, and burning in women who are experiencing menopause (change of life; the end of monthly menstrual periods). However, women who need a medication only to treat vaginal dryness, itching, or burning should consider a different treatment. These forms of estrogen injection are also sometimes used to treat the symptoms of low estrogen in young women who do not produce enough estrogen naturally. The estradiol valerate form of estrogen injection is also sometimes used to relieve the symptoms of certain types of prostate (a male reproductive organ) cancer. The conjugated estrogens form of estrogen injection is used to treat abnormal vaginal bleeding that a doctor has decided is caused only by a problem with the amounts of certain hormones in the body. Estrogen injection is in a class of medications called hormones. It works by replacing estrogen that is normally produced by the body.

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Evening Primrose - More Interactions

Evening Primrose interacts with 226 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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