Interaction Details

Medroxyprogesterone Acetate is classified as belonging to the following category: Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, red clover might increase levels of drugs metabolized by CYP3A4; however, a small clinical study found no effect.
In vitro evidence shows that red clover might inhibit CYP3A4 isoenzymes. However, a clinical study in healthy postmenopausal individuals shows that taking red clover capsules standardized to contain 60 mg isoflavones twice daily for 14 days does not affect the pharmacokinetics of alprazolam, a CYP3A4 probe substrate.

Interaction Rating


Likelihood of Occurrence


Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans.


  • Budzinski JW, Foster BC, Vandenhoek S, Arnason JT. An in vitro evaluation of human cytochrome P450 3A4 inhibition by selected commercial herbal extracts and tinctures. Phytomedicine 2000;7:273-82.
  • Unger M, Frank A. Simultaneous determination of the inhibitory potency of herbal extracts on the activity of six major cytochrome P450 enzymes using liquid chromatography/mass spectrometry and automated online extraction. Rapid Commun Mass Spectrom 2004;1
  • Chen L, Choi J, Leonard SW, et al. No Clinically Relevant Pharmacokinetic Interactions of a Red Clover Dietary Supplement with Cytochrome P450 Enzymes in Women. J Agric Food Chem. 2020;68(47):13929-13939.

Red Clover Overview

Red Clover Red clover (Trifolium pratense) is a perennial plant that is native to Europe and Asia, but is also found in many parts of the world, including North America. Red clover has a long history of use in traditional medicine and is believed to have a number of potential health benefits. It is a rich source of isoflavones, which are thought to have estrogen-like effects and is therefore often marketed for women's health. It has been used to treat hot flashes and other menopause symptoms as well as cardiovascular disease, high cholesterol, and osteoporosis.
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Medroxyprogesterone Acetate Overview

  • Medroxyprogesterone is used to treat abnormal menstruation (periods) or irregular vaginal bleeding. Medroxyprogesterone is also used to bring on a normal menstrual cycle in women who menstruated normally in the past but have not menstruated for at least 6 months and who are not pregnant or undergoing menopause (change of life). Medroxyprogesterone is also used to prevent overgrowth of the lining of the uterus (womb) and may decrease the risk of cancer of the uterus in patients who are taking estrogen. Medroxyprogesterone is in a class of medications called progestins. It works by stopping the growth of the lining of the uterus and by causing the uterus to produce certain hormones.

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Red Clover - More Interactions

Red Clover interacts with 820 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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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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