Federal regulators are reviewing 32 cases of serious liver injury in patients who are taking weight-loss drugs promoted by Roche Holding AG (RHHBY) and GlaxoSmithKline Plc (GSK).

The Food and Drug Administration (FDA) of the U. S., said that it received six reports of liver failure in patients who are taking the weight loss drug orlistat, sold as Alli by GlaxoSmithKline over-the-counter and in prescription form as Xenical by Roche.

The investigation is going on by FDA and no link has yet been found out between the liver injury and the weight loss drugs. Therefore the physicians have not been advised to change their prescription habits to treat such patients. Nevertheless, the FDA has raised an alert about the products as part of an effort to alert the public when it has concerns regarding the use of a product.

Alli has not been proved to cause damage to the liver as told by the Glaxo spokesperson, Deborah G. Bolding. She informed that the drug acts in the gastro-intestinal tract and is absorbed in the blood which implies that there is no evidence to suggest that Alli causes liver damage.

The common symptoms seen after the use of these drugs are yellowing of the skin or whites of the eyes, weakness and stomach pain. Obesity is quickly approaching the levels of an epidemic in the United States, making orlistat quiet popular.