Evening Primrose Oil

Are there any interactions with medications?



Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs)
Interaction Rating: Major Do not take this combination.

Evening primrose oil contains GLA (gamma-linolenic acid), which might slow blood clotting. Taking evening primrose oil along with medications that also slow clotting might increase the chances of bruising and bleeding.

Some medications that slow blood clotting include aspirin, clopidogrel (Plavix), nonsteroidal anti-inflammatory drugs (NSAIDs) such as diclofenac (Voltaren, Cataflam, others), ibuprofen (Advil, Motrin, others), naproxen (Anaprox, Naprosyn, others), dalteparin (Fragmin), enoxaparin (Lovenox), heparin, warfarin (Coumadin), and others.



Medications used during surgery (Anesthesia)
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.

Evening primrose oil might interact with medications used during surgery. One person who was taking evening primrose oil and other medications had a seizure during surgery. But there isn't enough information to know if evening primrose oil or the other medications caused the seizure. Be sure to tell your doctor what natural products you are taking before having surgery. To be on the safe side, you should stop taking evening primrose oil at least 2 weeks before surgery.



Phenothiazines
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.

Taking evening primrose oil with phenothiazines might increase the risk of having a seizure in some people.

Some phenothiazines include chlorpromazine (Thorazine), fluphenazine (Prolixin), trifluoperazine (Stelazine), thioridazine (Mellaril), and others.



Medications changed by the liver (Cytochrome P450 2C9 (CYP2C9) substrates)
Interaction Rating: Minor Be cautious with this combination.
Talk with your health provider.

Some medications are changed and broken down by the liver. Evening primrose oil might decrease how quickly the liver breaks down some medications. Taking evening primrose oil along with some medications that are changed by the liver might increase the effects and side effects of some medications. Before taking evening primrose oil, talk to your healthcare provider if you take any medications that are changed by the liver.

Some of these medications that are changed by the liver include celecoxib (Celebrex), diclofenac (Voltaren), fluvastatin (Lescol), glipizide (Glucotrol), ibuprofen (Advil, Motrin), irbesartan (Avapro), losartan (Cozaar), phenytoin (Dilantin), piroxicam (Feldene), tamoxifen (Nolvadex), tolbutamide (Tolinase), torsemide (Demadex), and S-warfarin (Coumadin).

Dosing considerations for Evening Primrose Oil.

The following doses have been studied in scientific research:

BY MOUTH:
  • For breast pain: 3-4 grams daily.

Therapeutic Research Faculty copyright

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