As the summer heats up, so does Walgreen Co.’s appetite for acquisitions.

Just a few weeks after announcing a $7 billion deal to acquire about 46% of Alliance Boots GmbH, a European pharmacy and health products retailer and one of the biggest drugstore chains in the United Kingdom, Walgreen now has plans to acquire Stephen L. LaFrance Holdings Inc., a regional U.S. pharmacy chain, in a deal valued at $438 million.

Stephen L. LaFrance is the parent company of 144 USA Drug, Super D Drug, May’s Drug, Med-X and Warehouse stores in Arkansas, Kansas, Mississippi, Missouri, New Jersey, Oklahoma and Tennessee. Stephen L. LaFrance offers some basic e-commerce services such as prescription refilling and online photo management services. As part of the deal, Walgreen, No. 33 in the 2012 Internet Retailer Top 500, will also acquire the company’s corporate offices, an Arkansas distribution center and certain wholesale and private label business assets.

The deal for Stephen L. LaFrance, which generates annual revenue of $825 million, is expected to close around Sept. 1, Walgreen says. Walgreen made the acquisition to strengthen its business base in many smaller towns in the Mid-South, Deep South and Plains states, says Walgreen CEO Greg Wasson. “This acquisition expands our business in an important region of the country,” Wasson says. “It will provide significant new pharmacy business for us in this region while also enabling us to bring the Walgreens experience to many additional smaller communities where USA Drug has developed strong operational expertise.”

Stephen L. LaFrance is Walgreen’s latest acquisition. In June 2011 Walgreen also completed a deal to purchase Drugstore.com for about $409 million.