RALEIGH, N.C.--(BUSINESS WIRE)--Salix Pharmaceuticals, Ltd. (NASDAQ:SLXP) today announced the availability of Xifaxan® (rifaximin) 550 mg tablets (www.Xifaxan550.com) for the reduction in risk of overt hepatic encephalopathy (HE) recurrence in patients 18 years of age or older. Those HE patients may now fill their Xifaxan 550 mg prescriptions in U.S. pharmacies and should speak with their doctors about this important treatment option. HE is a serious disorder caused by chronic liver failure resulting in neurologic impairments in cognition, mental status and motor function. Xifaxan 550 mg was approved by the U.S. Food and Drug Administration (FDA) on March 24, 2010 in a twice daily dose.