Salix Pharmaceuticals (SLXP)

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SALIX PHARMACEUTICALS REPORTS CONCURRENCE WITH FDA ON

CONTENT AND FORMAT OF THE PENDING RIFAXIMIN NDA IN THE

TREATMENT OF NON-CONSTIPATION IRRITABLE BOWEL SYNDROME

Previously-Agreed Upon Endpoints for Phase 3 Trials

TARGET 1 and TARGET 2 Confirmed

NDA Submission Continues to be on Track for First Half 2010

RALEIGH, NC December 10, 2009 – Salix Pharmaceuticals, Ltd. (NASDAQ:SLXP) today reported that the Company held a pre-NDA meeting on December 8, 2009 with the FDA to discuss the Company’s proposed new drug application (NDA) for rifaximin in the treatment of patients with non-constipation irritable bowel syndrome (non-C IBS). The purpose of the meeting was to discuss the completion of the Company’s non-C IBS Development Program, the results of two Phase 3 trials, TARGET 1 and TARGET 2, and to reach agreement on the content and format of the Company’s pending NDA.

“We are pleased with the results of our discussions with the FDA regarding our completed Phase 3 trials and our proposed NDA for rifaximin in the treatment of non-C IBS,” stated Bill Forbes, Pharm.D., Senior Vice President Research and Development and Chief Development Officer, Salix. “During our meeting, we were able to review the prior agreements reached with the Gastrointestinal Division. As expected, the agreements, including the protocol-specified primary and key secondary endpoints used in TARGET 1 and TARGET 2 as the basis of the review for marketing approval of rifaximin in non-C IBS, were confirmed. It has been known that the FDA’s Division of Gastroenterology Products (DGP), along with assistance from the Study Endpoint and Labeling

Development (SEALD) Team, have been developing a new guidance for the use of endpoints in IBS clinical trials. The Phase 3 trials were designed, in consultation with the Division, to investigate the utility of rifaximin in non-C IBS by assessing adequate relief of IBS symptoms, adequate relief of IBS-related bloating and other endpoints such as abdominal pain and stool consistency. We are pleased that a clear regulatory pathway for the review and potential approval of rifaximin in non-C IBS has been provided. We continue to target submission of the NDA during the first half of 2010.”

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SALIX PHARMACEUTICALS PREVIEWS AMERICAN COLLEGE OF

GASTROENTEROLOGY 2009 ANNUAL SCIENTIFIC MEETING

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SALIX PHARMACEUTICALS ACQUIRES U.S. RIGHT TO LUPIN’S

PROPRIETARY BIOADHESIVE TECHNOLOGY FOR EXTENDED RELEASE

RIFAXIMIN PRODUCT

Salix and Lupin to Collaborate in the Development and Commercialization of an Extended

Release Rifaximin Product

RALEIGH, NC October 5, 2009 – Salix Pharmaceuticals, Ltd. (NASDAQ:SLXP) today announced that as of September 30, 2009 Lupin Ltd. granted Salix the exclusive right in the United States to its bioadhesive drug delivery technology for use with rifaximin. Salix and Lupin have entered into a development, commercialization and license agreement under which the two companies will collaborate in the development and commercialization of a product incorporating rifaximin and utilizing Lupin’s proprietary technology. In connection with this agreement, Salix and Lupin have entered into an exclusive agreement in the United States for supply of rifaximin active pharmaceutical ingredient (API). Salix is required to make a $5 million up-front payment and regulatory milestone payments to Lupin, with the majority contingent upon achievement of clinical development and U.S. regulatory milestones. In addition, Salix will pay royalties on net sales of the bioadhesive rifaximin product.

Carolyn Logan, President and CEO, Salix, commented, “We are pleased to enter into this strategic collaboration with Lupin. This collaboration to develop and commercialize an extended release formulation of rifaximin is a significant advancement in rifaximin’s lifecycle management strategy. With this collaboration Salix embarks on the development of our next generation rifaximin product incorporating Lupin’s proprietary drug delivery platform with our

proprietary gut-targeted antibiotic. We believe this novel delivery approach, which combines controlled-release as well as slowed gastrointestinal transit of rifaximin, might prove to provide a number of clinical advantages including patient compliance and patient convenience. The acquisition of these rights to Lupin’s proprietary bioadhesive drug delivery technology should serve to further protect this important Company asset.”

Nilesh Gupta, Group President and Executive Director, Lupin, stated, “We are pleased to enter into this collaboration with Salix. We believe our proprietary bioadhesive drug delivery technology, which combines controlled-release as well as slowed gastrointestinal transit, could provide an extended release formulation of rifaximin that will be an important component of Salix’s lifecycle management strategy for rifaximin. This formulation, coupled with Salix’s commercialization capabilities, gives us the opportunity to jointly bring a potentially great product to the marketplace. We also believe that this alliance further validates Lupin’s increasing capabilities as a drug delivery provider. “

About XIFAXAN^® (rifaximin)

Rifaximin is a gut-selective antibiotic with negligible systemic absorption (<0.4%) and broad-spectrum activity in vitro against both gram-positive and gram-negative pathogens. Rifaximin has a similar tolerability profile to that of placebo. XIFAXAN revenue for 2008 was approximately $80 million.

Rifaximin tablets 200 mg, which Salix markets in the United States under the trade name XIFAXAN^® (rifaximin) tablets 200 mg, currently is approved for the treatment of patients, 12 years of age or older, with travelers’ diarrhea (TD) caused by non–invasive strains of Escherichia coli. XIFAXAN (rifaximin) is a gut–selective antibiotic with negligible systemic absorption (<0.4%) and broad–spectrum activity in vitro against both gram–positive and gram–negative pathogens. Rifaximin has a similar tolerability profile to that of placebo and has activity against the most common TD pathogens. XIFAXAN should not be used in patients with diarrhea complicated by fever or blood in the stool or diarrhea due to pathogens other than Escherichia coli. XIFAXAN should be discontinued if diarrhea symptoms get worse or persist more than 24–48 hours and alternative antibiotic therapy should be considered. In clinical trials, XIFAXAN was generally well tolerated. The most common side effects (vs. placebo) were flatulence 11.3% (versus 19.7%), headache 9.7% (versus 9.2%), abdominal pain 7.2% (versus 10.1 %) and rectal tenesmus 7.2% (versus 8.8%).

Rifaximin has been used in Italy for 24 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^®.

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SALIX PHARMACEUTICALS ANNOUNCES FDA ACCEPTANCE FOR

FILING AND PRIORITY REVIEW DESIGNATION FOR RIFAXIMIN NDA

FOR THE MAINTENANCE OF REMISSION OF HEPATIC

ENCEPHALOPATHY

RALEIGH, NC August 24, 2009 – Salix Pharmaceuticals, Ltd. (NASDAQ:SLXP) today announced the Food and Drug Administration (FDA) has accepted for filing and designated for Priority Review the Company’s New Drug Application (NDA) for rifaximin tablets 550 mg for the maintenance of remission of hepatic encephalopathy (HE). Additionally, the FDA has informed the Company of its plan to schedule an Advisory Committee meeting in late February 2010 to discuss the application.

A Priority Review classification is granted to drugs offering major advances in treatment, or providing a treatment where no adequate therapy exists. Based on this classification, the FDA has issued an action date of December 24, 2009 under the Prescription Drug User Fee Act (PDUFA). However, the convening of an Advisory Committee in late February 2010 signals the December 24, 2009 action date will be delayed.

“We are pleased with the FDA’s acceptance for filing of the rifaximin NDA and their decision to grant Priority Review for our application,” stated Bill Forbes, Pharm.D., Senior Vice President and Chief Development Officer, Salix Pharmaceuticals. “This review classification signals that the FDA considers that rifaximin has the potential to provide a significant advance in the treatment of hepatic encephalopathy. We are not surprised at the FDA’s decision to convene an Advisory Committee to gain an independent recommendation from outside experts regarding rifaximin due to the fact that, if approved, rifaximin will be the first new option approved for the

management of HE in over 30 years. We believe the availability of rifaximin has the potential to change the treatment paradigm for HE. Today’s news marks a milestone for Salix, rifaximin and patients suffering from this serious condition.”

Currently Salix estimates the U.S. commercial opportunity represented by the HE market is approximately $600 million. Hepatic encephalopathy occurs frequently in patients with cirrhosis as a result of their end-stage liver disease. Typically the cirrhosis is caused by a number of factors, such as alcohol and/or drug abuse, chronic viral hepatitis and autoimmune disease. Cirrhosis is a leading cause of death in the United States.¹ The number of cases of liver disease in the United States and around the world is rapidly increasing, with more than 7 million people in the United States being diagnosed with chronic liver disease.² There are reported to be more than 100,000 patients in the United States with overt HE.³

Rifaximin has been granted Orphan Drug designation by the FDA for use in hepatic encephalopathy. Salix believes this designation will provide seven years of marketing exclusivity in the United States if rifaximin gains approval from the FDA for HE.

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SALIX PRESENTS HIGHLY STATISTICALLY SIGNIFICANT RESULTS FROM THE PHASE III PIVOTAL STUDY OF RIFAXIMIN FOR THE PREVENTION AND MAINTENANCE OF REMISSION OF HEPATIC ENCEPHALOPATHY (HE)

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Salix Presents New Phase II Data Evidence Demonstrating the Clinical Utility of Rifaximin in Irritable Bowel Syndrome (IBS)

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