Can I take Evening primrose oil and Milk thistle extract together?
Drug interaction guide
Originally published 14 Mar 2026
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There are no known significant interactions between evening primrose oil and milk thistle extract when taken together at standard doses. Both are generally well-tolerated herbal supplements.
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Why this happens
These two supplements are processed by different pathways in the body. Evening primrose oil provides essential fatty acids (GLA), while milk thistle contains silymarin, which primarily affects liver cell stability. They do not appear to interfere with each other's absorption or metabolism.
What you should do
Back to contentsIt is generally safe to take these together. However, as with any supplement, you should inform your doctor or pharmacist if you are taking them alongside prescribed medications, particularly blood thinners or diabetes medication, as individual supplements can sometimes affect how those drugs work.
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Important precautions
Back to contentsEpilepsy or Schizophrenia
Evening primrose oil may increase the risk of seizures, particularly in people with temporal lobe epilepsy or those taking phenothiazine medications.
Surgery
Evening primrose oil can increase the risk of bleeding during and after surgery; you must stop taking it at least two weeks before any scheduled operation.
Hormone-sensitive conditions (e.g. breast or uterine cancer, endometriosis)
Milk thistle may have oestrogen-like effects which could worsen conditions sensitive to hormones.
Food and drink warnings
Back to contentsAlcohol
While there is no direct chemical interaction, milk thistle is often taken to support liver health. Consuming alcohol can cause further liver damage and may counteract the potential benefits of the supplement.
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Using other medicines
Back to contentsTaking multiple medicines? Our Medicines Interaction Checker helps you check whether your prescriptions, over-the-counter medicines, and supplements are safe to take together. Simply search for your medicines to see potential interactions and what to do about them.
Disclaimer
This information is for general educational purposes only and should not be relied upon as a substitute for professional medical advice. Always consult your GP, pharmacist, or another qualified healthcare professional before making decisions about your medications. Individual circumstances may vary, and only a healthcare professional who knows your medical history can provide personalised guidance.
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Article history
The information on this page is written and peer reviewed by qualified clinicians.
14 Mar 2026 | Originally published
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