FDA has sent warning letters to 23 U.S. companies and two individuals marketing a range of products that fraudulently claim to prevent and cure cancer, according to the agency.

FDA also warns North American consumers against using or purchasing the products, which include tablets, teas, tonics, black salves and creams, and are sold under various names on the Internet.

The products contain ingredients such as bloodroot, shark cartilage, coral calcium, cesium, ellagic acid, Cat’s Claw, an herbal tea called Essiac, and mushroom varieties such as Agaricus Blazeii, Shitake, Maitake, and Reishi.

According to FDA, because these products claim to cure, treat, mitigate or prevent disease, and they have not been shown to be safe and effective for their labeled conditions of use, they are unapproved new drugs marketed in violation of the Federal Food, Drug and Cosmetic Act.

The agency offers some examples of fraudulent claims for these products, including: “Treats all forms of cancer”; “Causes cancer cells to commit suicide!”; “80% more effective than the world’s number one cancer drug”; “Skin cancers disappear”; “Target cancer cells while leaving healthy cells alone”; “Shrinks malignant tumors”; “Avoid painful surgery, radiotherapy, chemotherapy, or other conventional treatments.”

“Although promotions of bogus cancer ‘cures’ have always been a problem, the Internet has provided a mechanism for them to flourish,” said Margaret O’K. Glavin, FDA’s associate commissioner for regulatory affairs. “These warning letters are an important step to ensure that consumers do not become the victim of false ‘cures’ that may cause greater harm to their health.”

The warning letters are part of FDA’s ongoing efforts, in collaboration with FTC and Canadian government agencies, to prevent deceptive products from reaching consumers. The initiative originated from consumer complaints and a web search for fraudulent cancer products conducted by FDA, FTC and members of the Mexico–U.S.–Canada Health Fraud Working Group. Earlier this year, FTC sent warning letters to 112 websites falsely promoting cancer “treatments” and referred several others to foreign authorities.