Common Names

  • Seasilver

For Patients & Caregivers

Seasilver does not prevent or cure cancer.

Promoters of seasilver claim that the product is effective against cancer and other diseases. There is no scientific evidence, in the form of laboratory studies, animal studies, or clinical trials, to support such claims.

In June, 2003 the Federal Trade Commission (FTC) accused Seasilver’s marketers of promoting Seasilver with false and fraudulent claims at which point the Food and Drug Administration (FDA) seized nearly $5.3 million worth of the product. Seasilver USA has since agreed to comply with strict FDA and FTC guidelines regarding the marketing of its product.

  • To detoxify the body
    No scientific evidence supports this use.
  • To prevent and treat cancer
    This claim is not backed by scientific evidence.
  • Many products that contain seaweed have been found to be contaminated.
  • Aloe vera, a component of SeasilverTM, is suspected to cause adverse effects when taken by mouth. The FDA rules that aloe is not safe as a stimulant laxative.
  • Certain compounds found in pau d’arco, another component of SeasilverTM, are known to cause toxic effects. There is no proof that pau d’arco can treat cancer or any other condition.
  • The FDA has issued warnings to the manufacturers of SeasilverTM to stop making false health claims for this product.
Back to top

For Healthcare Professionals

Seasilver™ (Seasilver USA, California, USA)

SeasilverTM is a dietary supplement that contains aloe vera, a combination of seaweed, pau d’arco, and cranberry concentrate. It has been promoted as a natural immune enhancer. While the exact properties of this product are unclear, certain ingredients may not be appropriate for cancer patients. Aloe vera contains anthraquinone which may irritate the GI system, leading to stomach upset and diarrhea. Certain seaweed products contain carrageenan and algin. At high doses these substances can impair absorption of oral medications. Many seaweed products have problems with contamination, which may pose a risk for immunocompromised patients. Pau d’arco is a bark that has potential anticoagulant effects due to coumarin content. Pau d’arco is typically prepared in 20% ethyl alcohol, but the final alcohol concentration of this product is not listed (1). Cranberry is acidic, and while the pH of this product is unknown, high concentrations may cause stomach irritation (3). No studies have shown the efficacy of this costly product, which is distributed through a multi-tiered marketing scheme.

In June 2003, the FDA seized nearly $5.3 millions worth of product from Seasilver USA’s San Diego headquarters (3). Since then Seasilver has agreed to comply with strict FDA and FTC guidelines regarding marketing of its product (4).

  • Cancer prevention
  • Detoxification
  • The FDA rules that aloe is not safe as a stimulant laxative.
  • Aloe vera taken for internal use should be discouraged due to possible adverse effects and inconclusive clinical data (1) (2).
  • Quinone compounds found in pau d’arco are known to possess toxic effects. The effectiveness of pau d’arco for the treatment of cancer or any other condition remains unproven and must not be recommended (1).

  1. Brinker F. Herb Contraindications and Drug Interactions, 2nd ed. Sandy (OR): Eclectic Med Publications; 1998.

  2. Bisset NG. Herbal Drugs and Phytopharmaceuticals. Boca Raton: CRC Press; 1994.

  3. Federal Trade Commission. No Silver Lining for Marketers of Bogus Supplement; Federal Agencies Crack Down on Health Fraud. June 19, 2003. Accessed February 6, 2014.

Back to top
Back to top
Email your questions and comments to

Last Updated