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Breast pain (mastalgia), breast cysts
Evening primrose oil is a popular treatment for breast pain in Europe. However, there are no high-quality scientific studies showing that it works. Studies of evening primrose oil for breast pain have yielded unclear results. Therefore, it cannot be recommended for either of these conditions.
Potential Dangers
Allergies
People with allergies to plants in the Onagraceae family may be allergic to evening primrose oil. People allergic to gamma-linolenic acid or any other ingredients in evening primrose oil should avoid its use. Contact dermatitis (skin rash) is possible.
Side Effects
There are reports of seizures with the use of evening primrose oil. People at risk of seizures should avoid using it. Evening primrose oil lowers blood pressure in animals, but effects in humans are not clear. Headache, stomach pain, nausea and loose stools may occur.
Pregnancy And Breast-Feeding
There is not enough information available to know if evening primrose oil is safe for pregnant or breast-feeding women.
Interactions
Interactions with drugs, supplements and other herbs have not been thoroughly studied. The interactions listed below have been reported in scientific publications. If you are taking prescription drugs, speak with a health care professional or pharmacist before using herbs or dietary supplements.
Interactions With Drugs
Evening primrose oil may cause seizures when taken with phenothiazine drugs such as chlorpromazine (Thorazine), thioridazine (Mellaril), trifluoperazine (Stelazine) or fluphenazine (Prolixin). There is a risk of seizure when used with anesthesia, and you may need to stop taking evening primrose oil before some surgeries. Patients taking drugs that increase the risk of seizures or drugs that prevent seizures should avoid evening primrose oil. In theory, this herb may add to the blood pressure-lowering effects of other drugs. Ask a health care professional or pharmacist for advice before you take evening primrose oil if you are taking any other drugs.
Interactions With Herbs And Dietary Supplements
The possibility of harmful effects when taking evening primrose oil with other herbs or supplements has not been well studied. Always read labels carefully, and speak with a health care professional before starting new therapies.
For Breast Pain (Mastalgia)
Adults (Aged 18 Or Older)
A dose of three grams daily, divided into two doses, has been taken by mouth.