Overview

Flaxseed oil comes from flaxseed (Linum usitatissimum). It is a good source of an essential omega-3 fatty acid called alpha-linolenic acid (ALA).

The alpha-linolenic acid and other chemicals in flaxseed oil seem to decrease swelling, which is why some people use it for conditions that involve inflammation, such as rheumatoid arthritis.

Flaxseed oil is used for heart disease, high blood pressure, high levels of cholesterol or other fats (lipids) in the blood (hyperlipidemia), and many other conditions, but there is no good scientific evidence to support these uses.

Flaxseed oil has different effects than whole or ground flaxseed. See Flaxseed for more information.



Uses & Effectiveness

Possibly Ineffective for

  • Bipolar disorder. Taking flaxseed oil by mouth doesn't seem to improve symptoms of mania or depression in children with bipolar disorder.
  • High levels of cholesterol or other fats (lipids) in the blood (hyperlipidemia). Taking flaxseed oil by mouth doesn't seem to reduce cholesterol.
  • Obesity. Taking flaxseed oil by mouth doesn't reduce body weight, body mass index, or waist size in overweight adults.
  • Rheumatoid arthritis (RA). Taking flaxseed oil by mouth daily doesn't seem to improve symptoms of pain and stiffness in people with RA.

There is interest in using flaxseed oil for a number of other purposes, but there isn't enough reliable information to say whether it might be helpful.

Side Effects

When taken by mouth: Flaxseed oil is likely safe for most adults. Supplements containing 2 grams of flaxseed oil daily have been used safely for up to 6 months. Higher doses of up to 24 grams daily have also been used safely for up to 7 weeks. These larger doses can cause side effects such as loose stools and diarrhea. Allergic reactions are also possible.

When applied to the skin: Flaxseed oil is possibly safe when used short-term. Flaxseed oil has been used safely on the wrist for up to 4 weeks.

When applied into the eye: Flaxseed oil is possibly safe when applied into the eye short-term. Eye drops containing flaxseed oil have been used safely for up to 3 months. Redness and itching may occur in some people.

Special Precautions and Warnings

When taken by mouth: Flaxseed oil is likely safe for most adults. Supplements containing 2 grams of flaxseed oil daily have been used safely for up to 6 months. Higher doses of up to 24 grams daily have also been used safely for up to 7 weeks. These larger doses can cause side effects such as loose stools and diarrhea. Allergic reactions are also possible.

When applied to the skin: Flaxseed oil is possibly safe when used short-term. Flaxseed oil has been used safely on the wrist for up to 4 weeks.

When applied into the eye: Flaxseed oil is possibly safe when applied into the eye short-term. Eye drops containing flaxseed oil have been used safely for up to 3 months. Redness and itching may occur in some people.

Pregnancy: Flaxseed oil is possibly safe when taken by mouth in doses of up to 2 grams daily for up to 6 weeks during pregnancy. But using flaxseed oil during the second or third trimester has been linked with an increased risk of giving birth prematurely.

Breast-feeding: There isn't enough reliable information to know if flaxseed oil is safe to use when breast-feeding. Stay on the safe side and avoid use.

Children: Flaxseed oil is possibly safe for children when taken by mouth, short-term. Flaxseed oil has been safely taken by mouth for up to 3 months by children about 7-8 years old.

Surgery: Flaxseed oil might increase the risk of bleeding during and after surgery. Stop using it at least 2 weeks before a scheduled surgery.

Interactions

    Moderate Interaction

    Be cautious with this combination

  • Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs) interacts with Flaxseed Oil

    Flaxseed oil might slow blood clotting. Taking flaxseed along with medications that also slow blood clotting might increase the risk of bruising and bleeding.

  • Ezetimibe (Zetia) interacts with Flaxseed Oil

    Flaxseed oil contains alpha-linolenic acid. Taking flaxseed oil and ezetimibe together can prevent the body from absorbing alpha-linolenic acid from flaxseed oil. If you are taking ezetimibe, talk to your doctor before taking flaxseed oil.

  • Medications for high blood pressure (Antihypertensive drugs) interacts with Flaxseed Oil

    Flaxseed oil might lower blood pressure. Taking flaxseed along with medications that lower blood pressure might cause blood pressure to go too low. Monitor your blood pressure closely.

Dosing

Flaxseed oil has most often been used by adults in doses of 1-2 grams by mouth daily for up to 6 months. Speak with a healthcare provider to find out what dose might be best for a specific condition.
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CONDITIONS OF USE AND IMPORTANT INFORMATION: This information is meant to supplement, not replace advice from your doctor or healthcare provider and is not meant to cover all possible uses, precautions, interactions or adverse effects. This information may not fit your specific health circumstances. Never delay or disregard seeking professional medical advice from your doctor or other qualified health care provider because of something you have read on WebMD. You should always speak with your doctor or health care professional before you start, stop, or change any prescribed part of your health care plan or treatment and to determine what course of therapy is right for you.

This copyrighted material is licensed from Therapeutic Research Center, LLC. Information from this source is evidence-based and objective, and without commercial influence. For professional medical information on natural medicines, see Natural Medicines Comprehensive Database Professional Version.
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