Bladderwrack (Julie Doan, Purdue College of Pharmacy

Jolie Doan Student Pharmacist Spring 2022

BLADDERWRACK

Scientific Name: Fucus Vesiculosus

Common Names: Bladderwrack, Black Tang, Rockweed, “Sea Grapes,” Bladder Fucus, Sea Oak, Cut Weed, Dyers Fucus, Red Fucus, Rock Wrack

Background and History

Bladderwrack is a brown seaweed that is grown in high salinity waters, such as the Baltic Sea. This seaweed belongs to a class of plants called Fucus Vesiculosus. In East Asia, this plant is harvested and used as a nutritional source of food for centuries. It is unknown as to when the use of bladderwrack began. Currently, it is also being used in fertilizers, animal nutrition, and pest control.

Purported Uses

Most Commonly Used For: • Inflammation • Hypothyroidism • Indigestion Other Uses: • Diabetes • Skin conditions • Cancers • Diarrhea • Constipation • Gastritis • Gastroesophageal Reflux Disease (GERD) • Heartburn • Wound Healing • Low Stomach Acidity • Weight Loss

https://www.google.com/url?sa=i&url=https%3A%2F%2Fdra xe.com%2Fnutrition%2Fbladderwrack%2F&psig=AOvVaw2m G6pGwW9A66v8A1Or7lf&ust=1645843014831000&source=imag es&cd=vfe&ved=0CAsQjRxqFwoTCOiOoK3pmfYCFQAAAAAd AAAAABAD

Mechanism of Action

Through the metabolism of bladderwrack, one metabolite belongs to the class of phlorotannins, a class of phenolic compounds that are found exclusively in marine organisms. The subclasses of phlorotannins related to bladderwrack is called fucols and fucophlorethols. These phenolic compounds produce antioxidant, antiinflammatory, antimicrobial, and antidiabetic properties.

It also contains high levels of iodine. Iodine produces thyroid hormones (T3 and T4) to help regulate metabolism and hypothyroidism. A lack of thyroid hormones causes the body to secrete thyroid stimulating hormone.

Doses and Dosage Forms

There is not much information regarding dosing of bladderwrack, so information that is found is through drug facts from store-bought bottles. Bladderwrack can be found in a few dosage forms: powdered, dried, capsules, or as a tea. Capsules: It is commonly seen throughout stores that bladderwrack is dosed at one capsule (580 MG) daily. Tea: Steep one bag for 4-5 minutes in eight ounces of hot water or add one teaspoon of dried bladderwrack to boiling water and allow it to simmer for 10-15 minutes.

There is currently not enough information to determine if bladderwrack is effective. There is one acute study in rodents that found no evidence of toxic effects after using bladderwrack for four weeks.

Warnings and Toxicity

It is found that bladderwrack interacts with amiodarone, ACE inhibitors, cytochrome P450 enzyme substrates, lamotrigine, Vitamin K anticoagulants (i.e., warfarin), non-steroidal anti-inflammatory products with antiplatelet and/or anticoagulant properties, and thrombolytic agents with antiplatelet and/or anticoagulant properties. Bladderwrack increases the risk of bleeding.

Information is limited towards the toxicity of bladderwrack. It could potentially be toxic due to heavy metal absorption of iodine.

Side Effects

There are currently not enough clinical studies to show the side effects of bladderwrack. One possible side effect may be a minor gastric adverse event, which includes soft feces and feelings of fullness.

https://www.google.com/u rl?sa=i&url=https%3A%2F% 2Fwww.vitaminshoppe.co m%2Fp%2Fsolaraybladderwrack-580mg-100capsules%2Fso7144&psig=AOvVaw1sw_0 oORRAjmnteAXPFvP4&ust= 1645842682104000&sourc e=images&cd=vfe&ved=0C AcQjRxqFwoTCNDSwPXnmf YCFQAAAAAdAAAAABAQ In the scientific article, “Fucaceae: A Source of Bioactive Phlorotannins,” it studies the class of fucus vesiculosus seaweeds and the health benefits that they provide. Phlorotannins are abundant in green seaweeds, like bladderwrack and produce the metabolite called phlorotannin. This study focused on the antioxidant effects, anti-diabetic effects, anti-tumor, and antiinflammatory effects. The phenolic compounds showed positive results for antioxidant activity through its scavenging activity and could inhibit xanthine oxidase. Phlorotannins also show to be effective inhibitors of αglycosidase and α-amylase, which work by preventing hydrolysis of carbohydrates in the body and prevent the blood sugar from rising. For its anti-inflammatory activity, it is shown to downregulate the LPS-induced inflammatory molecules, like IL-6 and IL-8. Through its anti-inflammatory properties and antioxidant activity, it is associated with anti-tumor properties by decreasing inflammation and oxidative elements in the body.

Personal Opinion

There is currently not enough evidence to prove the effectiveness of bladderwrack. In my professional opinion, I would not suggest people to take this product when there are other products that could help with the same issues. In addition to this, there are also many drug interactions with bladderwrack, where it increases the risk of bleeding. If there are people who are interested in trying the product, they should reach out to their physician before starting bladderwrack to make sure that they don’t face any side effects through this natural product. - J DOAN

References

1. Catarino M, Silva A, Cardoso S. Fucaceae: A source of bioactive phlorotannins. International Journal of Molecular

Sciences. 2017;18(6):1327. doi:10.3390/ijms18061327 2. BLADDERWRACK: Overview, uses, side effects, precautions, interactions, dosing and reviews. WebMD. https://www.webmd.com/vitamins/ai/ingredientmono-726/bladderwrack. Accessed February 25, 2022. 3. Bladderwrack. Drug Facts and Comparisons. Facts & Comparisons eAnswers. Wolters Kluwer Health, Inc. Riverwoods,

IL. Accessed February 25, 2022. http://online.factsandcomparisons.com 4. Davidson K. Bladderwrack: Benefits, uses, and side effects. Healthline. https://www.healthline.com/nutrition/bladderwrack-benefits#forms-dosage. Published July 8, 2020. Accessed

February 25, 2022. 5. Tennant L. Iodine & Thyroid Health: Are You Getting Enough?: Imaware™. imaware. https://www.imaware.health/blog/iodine-and-thyroidhealth#:~:text=Iodine%20is%20important%20for%20healthy,neck%20caused%20by%20elevated%20TSH. Published

June 4, 2021. Accessed February 25, 2022.