Bladderwrack

Medically reviewed by Drugs.com. Last updated on Nov 27, 2023.

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.
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:
- 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.
Signs of low blood pressure like feeling dizzy, weak, or tired; fainting; more thirst; or skin that is pale, cool, and clammy.
Swollen neck
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

2023-04-28

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