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Generic Name: flax (FLACKS)
Brand Name: Flax Seed Oil, Flax Oil

What is flax?

Flax is the seed of a plant called Linum usitatissimum, and is also known as Flax Seed, Alasi, Aliviraaii, Brown Flaxseed, Brown-Seeded Flax, Echter Lein, Flachssamen, Flax Hull, Flax Lignans, Gemeiner Flachs, Graine de Lin, Kattan, Keten, Leinsamen, Lignans, Lin, Oléagineux, Lin Textile, Linaza, Lini Semen, Linho, Lino, Linseed, Lint Bells, Linum, Malsag, Phytoestrogen, Ta Ma, Tisii, Winterlien, and other names.

Flax has been used in alternative medicine as a possibly effective aid in treating type 2 diabetes, high cholesterol, and some autoimmune diseases such as systemic lupus erythematosus (SLE).

Flax has also been used to treat osteoporosis. However, research has shown that flax may not be effective in treating this condition.

Other uses not proven with research have included enlarged prostate, heart disease, constipation, high blood pressure, irritable bowel syndrome, menopausal symptoms, weight loss, diverticulitis, attention deficit-hyperactivity disorder (ADHD), cancer (prostate, breast, lung, endometrial), and others.

It is not certain whether flax is effective in treating any medical condition. Medicinal use of this product has not been approved by the FDA. Flax should not be used in place of medication prescribed for you by your doctor.

Flax is often sold as an herbal supplement. There are no regulated manufacturing standards in place for many herbal compounds and some marketed supplements have been found to be contaminated with toxic metals or other drugs. Herbal/health supplements should be purchased from a reliable source to minimize the risk of contamination.

Flax may also be used for purposes not listed in this product guide.

What is the most important information I should know about flax?

Follow all directions on the product label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

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What should I discuss with my healthcare provider before taking flax?

Before using flax, talk to your healthcare provider. You may not be able to use flax if you have certain medical conditions.

Ask a doctor, pharmacist, or other healthcare provider if it is safe for you to use this product if you have:

  • a bleeding or blood-clotting disorder;

  • diabetes;

  • a gastrointestinal obstruction;

  • a hormone sensitive cancer or condition;

  • high triglyceride levels; or

  • high or low blood pressure.

Flax is considered likely unsafe to use during pregnancy.

It is not known whether flax passes into breast milk or if it could harm a nursing baby. Do not use this product without medical advice if you are breast-feeding a baby.

Do not give any herbal/health supplement to a child without medical advice.

How should I take flax?

When considering the use of herbal supplements, seek the advice of your doctor. You may also consider consulting a practitioner who is trained in the use of herbal/health supplements.

If you choose to use flax, use it as directed on the package or as directed by your doctor, pharmacist, or other healthcare provider. Do not use more of this product than is recommended on the label.

Do not use different formulations of flax (such as tablets, liquids, and others) at the same time, unless specifically directed to do so by a health care professional. Using different formulations together increases the risk of an overdose.

Call your doctor if the condition you are treating with flax does not improve, or if it gets worse while using this product.

Flax can affect blood-clotting and may increase your risk of bleeding. If you need surgery, dental work, or a medical procedure, stop taking flax at least 2 weeks ahead of time.

Store at room temperature away from moisture and heat.

Drink plenty of water each day while you are taking this product.

What happens if I miss a dose?

Skip the missed dose if it is almost time for your next scheduled dose. Do not use extra flax to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking flax?

Follow your healthcare provider's instructions about any restrictions on food, beverages, or activity.

Avoid using flax together with other herbal/health supplements that can also affect blood-clotting. This includes angelica (dong quai), capsicum, clove, danshen, garlic, ginger, ginkgo, horse chestnut, panax ginseng, poplar, red clover, saw palmetto, turmeric, and willow.

Avoid using flax together with other herbal/health supplements that can lower blood sugar, such as alpha-lipoic acid, chromium, devil's claw, fenugreek, garlic, guar gum, horse chestnut, Panax ginseng, psyllium, Siberian ginseng, and others.

Flax side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Although not all side effects are known, flax is thought to be likely safe for most people when taken by mouth.

Stop using flax and call your healthcare provider at once if you have:

  • any bleeding that does not stop.

Common side effects may include:

  • bloating, gas, stomach ache, constipation, diarrhea, and nausea.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

What other drugs will affect flax?

Other drugs may interact with flax, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.

Do not take flax without medical advice if you are using any of the following medications:

  • any medications for diabetes or high blood pressure;

  • an antibiotic;

  • estrogens;

  • a blood thinner (warfarin, Coumadin);

  • acetaminophen (Tylenol);

  • furosemide (Lasix);

  • any oral medications.

This list is not complete. Other drugs may interact with flax, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this product guide.

Where can I get more information?

  • Consult with a licensed healthcare professional before using any herbal/health supplement. Whether you are treated by a medical doctor or a practitioner trained in the use of natural medicines/supplements, make sure all your healthcare providers know about all of your medical conditions and treatments.
  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
  • Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2012 Cerner Multum, Inc. Version: 5.01. Revision Date: 2015-08-03, 10:57:29 AM.