Bladderwrack, or as it is more commonly called, kelp, is native to the salty waters of the Atlantic and Pacific oceans, according to Medicinal Herb Info. The entire plant is used to make medicinal treatments and it has a long history of medicinal use. Before taking kelp or giving it to a child, consult with your health care provider.
Bladderwrack Uses
The website for the U.S. National Library of Medicine, or USNLM, reports that kelp is a rich source of iodine and is commonly used to treat cancer, goiter and diabetes, as well as for its antifungal, antibacterial, blood thinning and antioxidant properties. The websit of the Memorial Sloan-Kettering Cancer Center, MSKCC, adds that kelp is useful for skin care, hypothyroidism, fatigue and menstrual problems. However, both sites caution against giving it to children due to the lack of information about its safety.
Research
The research mentioned for kelp on the USNLM website reports mixed results for kelp as an effective medicinal treatment. The site suggests a need for more clinical study of its effects and safety. Another recent study is described on the Complementary Prescriptions website with some serious warnings involved. This study explains that some kelp supplements may be contaminated with arsenic and other heavy metals. According to a sampling of nine popular kelp supplements, eight out of the nine contained dangerous levels of arsenic and other heavy metals. This study indicates that it may be safer to take other forms of iodine supplements, especially for children.
Possible Side Effects
According to the USNLM site, users of bladderwrack may experience acne-type skin lesions, upset stomach, metallic taste and increased salivation. The kelp may also cause laxative effects, as well. The site recommends that pregnant and breast-feeding women avoid the use of kelp and that it should not be given to children.
Potential Interactions
There are some potential interactions that could occur between kelp and other medications and supplements you may be taking. The USNLM website cautions people who take thyroid medications, lithium, hormone supplements or hormonal drugs, diabetes medications, blood thinners, non-steroidal anti-inflammatory drugs such as ibuprofen or naproxen, laxatives or diuretics to avoid also taking kelp supplements. If you have questions about whether supplements or medications you take could harmfully interact with kelp, talk to your pharmacist or health care provider.
Considerations
The USNLM site says that kelp may cause allergic reactions in some people. These allergic reactions can occur even if kelp has been taken before with no reaction. Watch for signs of swelling of the lips, tongue, face or throat when using kelp supplements. If any of these occur, stop taking it and contact your health care provider.



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