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Bladderwrack

Medically reviewed by Drugs.com. Last updated on Mar 10, 2022.

What are other common names?

  • Ascophyllum nodosum
  • Fucus vesiculosis
  • Atlantic Kelp
  • Black Tang
  • Bladder Fucus
  • Bladder Wrack
  • Blasentang
  • Cutweed
  • Fucus
  • Kelp
  • Kelpware
  • Knotted Wrack
  • Laminaire
  • Marine Oak
  • Norwegian Seaweed
  • Ocean Kelp
  • Rockweed
  • Rockwrack
  • Sea Kelp
  • Seaweed
  • Seawrack
  • Tang
  • Varech

What is this product used for?

Bladderwrack is a type of seaweed and is used by some people as a food source. It is also sold as a dietary supplement product. Information from medical studies does not support the use of bladderwrack for any health problem.

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.

  • This product may interfere with some lab tests. Be sure to talk with your doctor about this and all drugs you are taking.

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

  • 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 breastfeeding.

  • Do not give this product to children.

  • Take extra care if you are taking drugs that contain hormones. These are drugs like birth control pills and hormone replacement therapy.

  • Take extra care if you are allergic to iodine or take drugs that increase iodine in your body.

  • 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.

  • Take extra care if you are taking drugs for your thyroid. These are drugs like levothyroxine, thyroid desiccated, or liotrix.

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

    • Thyroid problems

    • Bleeding problems

    • Diabetes

What should I watch for?

  • Upset stomach

  • Stomach cramps

  • Rash

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 thyroid problems. These include unexplained weight loss, fast heartbeat, or shakiness.

  • Signs of high blood pressure. These include very bad headaches, nervousness, problems breathing, or nosebleeds.

  • Swollen neck

  • Very bad throwing up

  • Very bad belly pain

  • Very bad loose stools

  • Bruising or bleeding that is not normal

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

Last Reviewed Date

2021-03-26

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Further information

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