The US Food and Drug Administration (FDA) has sent warning letters to 15 companies, accusing those firms of illegally marketing products they claim can help cure, prevent or treat the symptoms of diabetes in violation of federal law. According to Reuters reporter Toni Clarke, the health regulators issued warnings to 10 domestic firms and five foreign companies producing a total of 20 different products. Those products are being sold online and in retail outlets, Clarke said, though it was unable to determine how many shops carried them or how many units had been distributed online. “The FDA is advising consumers not to use these or similar products because they may contain harmful ingredients or may be otherwise unsafe, or may improperly be marketed as over-the-counter products when they should be marketed as prescription products,” the agency said in a statement. “Using these products could cause consumers to delay seeking proper medical treatment for their diabetes.” Three of the most potentially harmful products originated from Asia and contained ingredients that were not disclosed on the product labels, Clarke said. They include: Diexi, marketed as an herbal formula from Amrutam Life Care in India that actually contained the diabetes drug metformin; Insupro Forte, a Malaysian substance that contains the FDA-approved substance glyburide, which can cause serious side effects is not used properly; and Jiang Tan Yi Huo Su Jiao Nang, a Chinese remedy found to contain both metformin and glyburide as well as phenformin, a substance pulled from the market in the US in 1978 because it had been linked to a condition known as lactic acidosis. The agency said they are not currently aware of any injuries or illnesses linked to the offending products, but said they are acting in order to protect the public health from potential harm linked to the substances. FDA officials also noted they have requested written responses from each of the companies within 15 business days, and that failure to correct the violations could result in product seizure, criminal prosecution or other legal action. “Diabetes is a serious chronic condition that should be properly managed using safe and effective FDA-approved treatments,” FDA Commissioner Margaret A. Hamburg said. “Consumers who buy violative products that claim to be treatments are not only putting themselves at risk but also may not be seeking necessary medical attention, which could affect their diabetes management.” More than 25 million US residents have diabetes, a condition in which a patient’s blood glucose or blood sugar levels are high as a result of the body’s inability to produce or effectively utilize insulin, the agency said. If the disease is not managed properly, there is an increased risk for heart disease, blindness, kidney failure, lower-extremity amputations or other serious medical complications, the FDA added.