Clostridium difficile-associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents, including XIFAXAN and may range in severity from mild diarrhea to fatal colitis. Treatment with antibacterial agents alters the normal flora of the colon which may lead to overgrowth of C. difficile. If CDAD is suspected or confirmed, ongoing antibiotic use not directed against C. difficile may need to be discontinued.The most common adverse reactions occurring in greater than eight percent of patients in the clinical study were edema peripheral (15 percent), nausea (14 percent), dizziness (13 percent), fatigue (12 percent), ascites (11 percent), muscle spasms (nine percent), pruritus (nine percent) and abdominal pain (nine percent). Rifaximin is a gut-selective antibiotic with negligible systemic absorption and broad-spectrum activity in vitro against both Gram-positive and Gram-negative pathogens. Rifaximin has a similar tolerability profile to that of placebo. Rifaximin has been used in Italy for 25 years and is approved in 33 countries. Salix acquired rights to market rifaximin in North America from Alfa Wassermann S.p.A. in Bologna, Italy. Alfa Wassermann markets rifaximin in Italy under the trade name Normix ®. About Salix Pharmaceuticals Salix Pharmaceuticals, Ltd., headquartered in Raleigh, North Carolina, develops and markets prescription products for the prevention and treatment of gastrointestinal diseases. Salix’s strategy is to in-license late-stage or marketed proprietary therapeutic products, complete any required development and regulatory submission and market them through the Company’s gastroenterology specialty sales and marketing team. Salix markets XIFAXAN ® (rifaximin) 550 mg and 200 mg tablets, MOVIPREP ® (PEG 3350, Sodium Sulfate, Sodium Chloride, Potassium Chloride, Sodium Ascorbate and Ascorbic Acid for Oral Solution), OSMOPREP ® (sodium phosphate monobasic monohydrate, USP and sodium phosphate dibasic anhydrous, USP) Tablets, APRISO ® (mesalamine) extended-release capsules 0.375 g, METOZOLV ® ODT (metoclopramide HCl), RELISTOR ® (methylnaltrexone bromide) Subcutaneous Injection, SOLESTA ®, DEFLUX ®, PEPCID ® (famotidine) for Oral Suspension, Oral Suspension DIURIL ® (Chlorothiazide), AZASAN ® (Azathioprine) Tablets, USP, 75/100 mg, ANUSOL-HC ® 2.5% (Hydrocortisone Cream, USP), ANUSOL-HC ® 25 mg Suppository (Hydrocortisone Acetate), PROCTOCORT ® Cream (Hydrocortisone Cream, USP) 1% and PROCTOCORT ® Suppository (Hydrocortisone Acetate Rectal Suppositories) 30 mg. Crofelemer, budesonide foam, RELISTOR ® , Lumacan ® and rifaximin for additional indications are under development. For full prescribing information and important safety information on Salix products, including BOXED WARNINGS for OSMOPREP, AZASAN and METOZOLV, please visit www.salix.com where the Company promptly posts press releases, SEC filings and other important information or contact the Company at 919 862-1000. Salix trades on the NASDAQ Global Select Market under the ticker symbol “SLXP”.