Bladderwrack – Uses and Benefits

Alternative Names:

Kelp, Black-tang, Bladder,Bladder fucus,Sea wrack, Blasen-tang, Brown algae, Common seawrack, Cut weed, Dyers fucus,Edible seaweed, Fucoidan,Black tang, Rockweed, Kelp-ware, Quercus marina, Cutweed,Blasentang, Seetang.

Herb Description

Bladderwrack is perennial that matures on the northern coasts of the Atlantic & Pacific oceans, the North and Baltic seas and is often washed up on beaches after storms.It is a common algae in the shape of long ribbons, about 1 meter long and 5cm across, leathery, shiny, brownish-green or light yellow in colour.The main stem of bladderwrack, called as the thallus, is used for various treatment. The frond at the bottom is fan-shaped, narrow & strap-shaped , the rest flat and leaf-like in shape, wavy, many times parted into 2 with erect divisions contain a strong, broad, compressed midrib running to the apex.

As a herbal remedy, bladderwrack has been used for traditional cosmetics, treatments for headaches , ulcers,asthma, cough, hemorrhoid, boils, goiters, stomach ailments, urinary problems, decreasing the incidence of tumors.The Vietnamese use bladderwrack as meal in various ways: pickle with sauce or with vinegar,raw as salad & vegetable, relish or sweetened jellies & also cooked for vegetable soup.

Bladderwrack contains moderate quantity of phosphorus, selenium, manganese and zinc and small amounts of vitamins A, C, E and G.But have a high content of several minerals such as iodine,sodium, calcium, magnesium, potassium, sulfur, silicon & iron and high in some B-complex vitamins.


  • Antibacterial.
  • Antioxidant.
  • Diuretic.
  • Emollient.
  • Endocrine tonic.
  • Expectorant.
  • Nutritive.
  • Anti-hypothyroid.
  • Thyroactive.
  • Anti-obesic.
  • Anti rheumatic.
  • Demulcent.
  • Gentle metabolic stimulant.
  • Adaptagen.
  • Anti-inflammatory.

Uses and Benefits

Bladderwrack has an advantage to treat the symptoms of rheumatoid arthritis & rheumatism , both used as an external & internal application upon inflamed joints.It has great benefit to cure active thyroid glands & goiter. This plant may be very useful to mitigate the excess weight,Where obesity is combined with thyroid problem.

Bladderwrack may decrease the blood cholesterol levels in the body possibly due to its fiber content and binding action.It enhance stamina by allowing cells to consume energy efficiently.Ebb irritation due to presence of putrefaction.

Bladderwrack have a toxic action on some strains of E. coli & all strains tested of Neisseria meningitidis. It have fucoidan that inhibits the growth of some unfriendly bacteria and viruses.

Side Effects

Large dosage may cause hyperthyroidism, tremor , increased pulse rate & elevated blood pressure .So it is recommended that bladder wrack should not be taken in cases of cardiac problems, or during pregnancy and lactation .

As bladderwrack grow in heavy-metal-contaminated water,It may have high levels of toxins such as arsenic and lead, causing to nerve damage, kidney damage, or other problems.

Scientific research reported the effects of iodine toxicity,the high iodine amount in bladderwrack may cause abnormal thyroid conditions & increased hyperthyroidism and reduced hypothyroidism from ingestion of kelp products.Bladderwrack have high content of iodine, heavy metal .Its use should always been considered potentially unsafe.


  • Dried bladderwrack:

5-10 gm or by infusion. Thrice a day.

  • Liquid Extract:

1:1 in 25% alcohol, 4-8ml . Thrice a day.

Drug Interactions

Based on scientific study, bladderwrack may have anticoagulant properties. Therefore, bladderwrack may enhance the risk of bleeding when taken with drugs in the same time that increase the risk of bleeding.

Some examples are as follows:

  • Aspirin.
  • Warfarin.
  • Heparin.
  • Clopidogrel.