Evening Primrose Oil … Safety & Interactions

Evening primrose oil may add to anticoagulant or antiplatelet effects and increase bleeding time. Human data also suggest higher antiretroviral levels, while a possible blood pressure effect remains uncertain.

Contraindications

  • Pregnancy without obstetric guidance
  • Active bleeding disorders or use before surgery without medical guidance

Cautions

  • Abdominal pain, nausea, diarrhea, indigestion, and headache can occur.
  • Pregnancy data are inconclusive, and attempted labor induction has produced inconsistent results and complications.
  • Commercial products may contain additional ingredients with different safety profiles.

Drug Interactions

Drug Class / Substrate Mechanism Severity Source
Anticoagulants and antiplatelet medicines Gamma-linolenic acid may reduce platelet activity and increase bleeding time. Major Memorial Sloan Kettering About Herbs
Antiretroviral medicines Human research found increased antiretroviral levels and a possible increase in adverse effects. Moderate Memorial Sloan Kettering About Herbs
Blood pressure medicines Population data associate evening primrose oil with increased blood pressure, but a direct medication interaction has not been established. Uncertain Memorial Sloan Kettering About Herbs

Pregnancy

Not recommended during pregnancy. Consult a qualified healthcare provider before any use.

This information is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider before using herbal medicines, especially if you take prescription medications.