For the second time in three months, FDA has expanded its nationwide alert to consumers about tainted weight loss products containing undeclared, active pharmaceutical ingredients.

The agency has identified additional weight loss products (Herbal Xenicol, Slimbionic and Xsvelten) as well as new undeclared active pharmaceutical ingredients (fenproporex, fluoxetine, furosemide and cetilistat). The current list now includes 72 products.

Previously, FDA laboratory tests revealed the presence of sibutramine, bumetanide, phenytoin, rimonabant and phenolphthalein in other over-the-counter (OTC) weight loss products.

“These tainted weight loss products pose a great risk to public health because they contain undeclared ingredients and, in some cases, contain prescription drugs in amounts that greatly exceed maximum recommended dosages,” said Janet Woodcock, MD, director of FDA’s Center for Drug Evaluation and Research. “Consumers have no way of knowing that these products contain dangerous drugs that could cause serious consequences to their health.”

On Dec. 22, 2008, FDA warned consumers not to purchase or consume 28 different products marketed for weight loss. On Jan. 8, 2009, FDA expanded the list to include 41 additional tainted products. The agency will continue to update this list as warranted.

The products identified, some of which are marketed as dietary supplements, are promoted and sold on various websites and in some retail stores and beauty salons. Some of the products claim to be “natural” or to contain only “herbal” ingredients, but actually contain potentially harmful ingredients not listed on the products’ labels or in promotional advertisements, according to FDA.

The agency has inspected a number of companies associated with the sale of these illegal products and is currently seeking product recalls. Based on inspections and the companies’ inadequate responses to recall requests, FDA may take additional enforcement steps, such as issuing warning letters or initiating seizures, injunctions, or criminal charges.

FDA advises consumers who have used any products containing these ingredients to stop taking them and consult their healthcare professional immediately. The health risks posed by these products can be very serious and include high blood pressure, seizures, tachycardia (rapid heartbeat), palpitations, heart attack and stroke.