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Medically reviewed by Last updated on Nov 27, 2021.

What are other common names?

  • Linum crepitans
  • Linum humile
  • Linum usitatissimum
  • Alasi
  • Brown Flaxseed
  • Brown-Seeded Flax
  • Common Flax
  • Flax Hull
  • Flax Lignans
  • Flax Meal
  • Flax Seed
  • Flaxseed
  • Flaxseed Oil
  • Golden Flax
  • Linseed
  • Linseed Flax
  • Linseed Oil
  • Lint Bells
  • Lintbells
  • Linum
  • Malsaga
  • Phytoestrogen
  • Ta Ma

What is this product used for?

Flaxseed, but not flaxseed oil, is a source of fiber. Flaxseed and flaxseed oil are used as a laxative. Flaxseed may help lower blood sugar, blood pressure, and cholesterol. Grind whole flaxseed for best results.

What are the precautions when taking this product?

  • Always check with your doctor before you use a natural product. Some products may not mix well with drugs or other natural products.

  • Do not use this product if you are pregnant or plan to become pregnant soon. Use birth control you can trust while taking this product.

  • Do not use this product if you are breast-feeding.

  • Take oral drugs 1 hour before flaxseed or 2 hours after flaxseed.

  • Be sure to take this product with plenty of water.

  • Be sure to tell your doctor that you take this product if you are scheduled for surgery or tests.

  • Take extra care if you are taking drugs to thin your blood. These are drugs like warfarin, heparin, or enoxaparin.

  • Take extra care if you are taking drugs to dissolve blood clots. These are drugs like alteplase, reteplase, or streptokinase.

  • Take extra care if you are taking drugs to help with swelling or inflammation. These are drugs like nonsteroidal anti-inflammatory drugs (NSAIDs), aspirin, ibuprofen, or naproxen.

  • Do not use this product if you have health problems that are sensitive to hormones. These are problems like breast cancer, prostate cancer, or endometriosis.

  • If you have blood sugar problems, keep hard candies, glucose tablets, liquid glucose, or juice on hand for low blood sugar.

  • Take extra care and check with your doctor if you have:

    • Bowel problems

    • Bleeding problems

    • Blood pressure problems

    • Diabetes

    • Cancer

    • Endometriosis or fibroids

What should I watch for?

  • Upset stomach

  • More stools than normal

  • Bloating

  • Increased gas

  • Heartburn

  • Itching

  • Stuffy nose

When do I need to call the doctor?

  • Signs of a very bad reaction. These include wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat. Go to the ER right away.

  • Signs of low blood sugar. These include hunger, dizziness, shaking, a fast heartbeat, confusion, or sweating.

  • Signs of low blood pressure like feeling dizzy, weak, or tired, fainting, more thirst, or skin that is pale, cool, and clammy.

  • Very bad throwing up

  • Very bad belly pain

  • Very bad loose stools

  • Very bad hard stools

  • Enlargement of breasts

  • Bruising or bleeding that is not normal

  • Changes in menstrual periods like lots of bleeding, spotting, or bleeding between cycles

Where can I learn more?

National Center for Complementary and Integrative Health

Last Reviewed Date


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