Exhibit 99.1

Contact:                                                Barbara Brungess

610-727-7199

bbrungess@amerisourcebergen.com

AMERISOURCEBERGEN NAMES TIM G. GUTTMAN

SENIOR VICE PRESIDENT AND CHIEF FINANCIAL OFFICER

VALLEY FORGE, PA, May 11, 2012 —AmerisourceBergen Corporation (NYSE: ABC) today announced that Tim G. Guttman, 53, has been named Senior Vice President and Chief Financial Officer, effective immediately.  Guttman will report to Steven H. Collis, AmerisourceBergen’s President and Chief Executive Officer.  He had been serving as the Company’s Acting Chief Financial Officer since February 13, 2012, and was Vice President and Corporate Controller since joining AmerisourceBergen in 2002.

“I am very pleased to appoint Tim to his new role,” said Collis.  “Since he joined the Company 10 years ago, he has demonstrated his ability to drive financial discipline throughout the organization, and he has been an important partner in driving our operating performance.  He brings a thorough knowledge of our business as well as unique perspectives from other industries to our leadership team, and I am confident that he will continue to play a key role in our future success.”

“I am excited to be taking this new role and to continue to help drive strong financial performance and deliver value to our shareholders,” said Guttman.  “We have tremendous opportunities ahead, driven by the growth areas of the markets we serve, and the unique services we provide to manufacturers and healthcare providers.  In addition, our demonstrated expense and working capital discipline, as well as our strong balance sheet give us excellent financial flexibility.”

Prior to joining AmerisourceBergen, Guttman was Vice President of Finance at Syncor International Corporation, and also previously held financial planning and managerial positions at Disney Consumer Products, Pizza Hut, Inc., and PepsiCo, Inc. He also spent seven years with the accounting firm of Deloitte & Touche.

Mr. Guttman graduated from The Ohio State University and earned his Master of Business Administration degree from The University of Texas.

The Company expects to fill the role of Corporate Controller internally.

About AmerisourceBergen

AmerisourceBergen is one of the world’s largest pharmaceutical services companies serving the United States, Canada and selected global markets. Servicing both healthcare providers and pharmaceutical manufacturers in the pharmaceutical supply channel, the Company provides drug distribution and related services designed to reduce costs and improve patient outcomes. AmerisourceBergen’s service solutions range from niche premium logistics and pharmaceutical packaging to reimbursement and pharmaceutical consulting services. With more than $80 billion in annual revenue, AmerisourceBergen is headquartered in Valley Forge, PA, and employs approximately 13,000 people. AmerisourceBergen is ranked #29 on the Fortune 500 list. For more information, go to www.amerisourcebergen.com.

Forward-Looking Statements

Certain of the statements contained in this press release are “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. These statements are based on management’s current expectations and are subject to uncertainty and change in circumstances. Among the factors that could cause actual results to differ materially from those projected, anticipated or implied are the following: changes in pharmaceutical market growth rates; the loss of one or more key customer or supplier relationships; changes in customer mix; customer delinquencies, defaults or insolvencies; supplier defaults or insolvencies; changes in pharmaceutical manufacturers’ pricing and distribution policies or practices; adverse resolution of any contract or other dispute with customers or suppliers; federal and state government enforcement initiatives to detect and prevent suspicious orders of controlled substances and the diversion of controlled substances; qui tam litigation for alleged violations of fraud and abuse laws and regulations and/or any other laws and regulations governing the marketing, sale and purchase of pharmaceutical products or services and any related litigation, including shareholder derivative lawsuits; changes in federal and state legislation or regulatory action affecting pharmaceutical product pricing or reimbursement policies, including under Medicaid and Medicare; changes in regulatory or clinical medical guidelines and/or labeling for the pharmaceutical products we distribute, including certain anemia products; price inflation in branded pharmaceuticals and price deflation in generics; greater or less than anticipated benefit from launches of the generic versions of previously patented pharmaceutical products; significant breakdown or interruption of our information technology systems; our inability to continue to implement an enterprise resource planning (ERP) system to handle business and financial processes and transactions (including processes and transactions relating to our customers and suppliers) of AmerisourceBergen Drug Corporation operations as intended without functional problems, unanticipated delays and/or cost overruns; success of integration, restructuring or systems initiatives; interest rate and foreign currency exchange rate fluctuations; economic, business, competitive and/or regulatory developments in Canada, the United Kingdom and elsewhere outside of the United States, including changes and/or potential changes in Canadian provincial legislation affecting pharmaceutical product pricing or service fees or regulatory action by provincial authorities in Canada to lower pharmaceutical product pricing and service fees; the impact of divestitures or the acquisition of businesses that do not perform as we expect or that are difficult for us to integrate or control; our inability to successfully complete any other transaction that we may wish to pursue from time to time; changes in tax laws or legislative initiatives that could adversely affect our tax positions and/or our tax liabilities or adverse resolution of challenges to our tax positions; increased costs of maintaining, or reductions in our ability to maintain, adequate liquidity and financing sources; volatility and deterioration of the capital and credit markets; and other economic, business, competitive, legal, tax, regulatory and/or operational factors affecting our business generally. Certain additional factors that management believes could cause actual outcomes and results to differ materially from those described in forward-looking statements are set forth (i) in Item 1A (Risk Factors) in the Company’s Annual Report on Form 10-K for the fiscal year ended September 30, 2011 and elsewhere in that report and (ii) in other reports filed by the Company pursuant to the Securities Exchange Act of 1934.

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