Here is a list of warning letters that the U.S. Food and Drug Administration has sent to companies whose offerings have included products alleged to be helpful against fibromyalgia. A warning letter is a serious notice to that a marketer appears to be violating federal law and may be subject to enforcement action if the apparent violation continues. Enforcement actions include seizure of goods, injunctions, criminal prosecutions, fines, and imprisonment.
Most sellers do what the FDA requests. In some cases, the product must be removed from the marketplace. In others, marketing can continue as long as the claims to which the FDA objected are stopped. Regardless of the outcome, it is wise to assume that the product is unlikely to help.