Nov 29 - Standard & Poor's Ratings Services said today that it assigned U.S.-based medical products and pharmaceutical distributor McKesson Corp.'s proposed senior unsecured notes offering its 'A-' issue-level rating. The notes will be issued in two tranches, and terms of the proposed notes, including maturities, amounts, and rates, will be determined by market conditions. The notes will rank equally with the company's existing and future unsecured and unsubordinated indebtedness. McKesson will use the proceeds from the notes to prefund the repayment of its $500 million 5.25% notes due March 1, 2013, and replenish working capital. The additional debt is not sufficient enough to alter our ratings or outlook on the company, and is in line with our expectations for the company's long-term capital structure. The ratings on McKesson reflect Standard & Poor's Ratings Services' assessment of the company's business risk profile as "satisfactory" given the company's leading position in a very stable industry and its financial risk profile as "modest" given its strong credit metrics and exceptional liquidity. Furthermore, we believe that the pending $2.1 billion acquisition of PSS World Medical Inc. is a logical extension of McKesson's existing medical products distribution business, and we do not expect McKesson to breach or operate above our previously published threshold for a "modest" financial risk profile of 2x debt to EBITDA for an extended period of time. RELATED CRITERIA AND RESEARCH -- Business Risk/Financial Risk Matrix Expanded, May 27, 2009 -- 2008 Corporate Criteria: Analytical Methodology, April 15, 2008 -- 2008 Corporate Criteria: Rating Each Issue, April 15, 2008 RATINGS LIST Ratings Unchanged McKesson Corp. Corporate Credit Rating A-/Stable/A-1 New Ratings McKesson Corp. Senior Unsecured Notes A- Complete ratings information is available to subscribers of RatingsDirect on the Global Credit Portal at www.globalcreditportal.com. All ratings affected by this rating action can be found on Standard & Poor's public Web site at www.standardandpoors.com. Use the Ratings search box located in the left column.