Walgreen said its moves will lead to a "faster and more agile company." It expects to book pre-tax charges for the restructuring of between $1.6 billion and $1.8 billion as it implements the program.
Late last year, Walgreens completed a nearly $16 billion deal to purchase the remaining stake of European health and beauty retailer Alliance Boots that it didn't already own. The company was renamed Walgreens Boots Alliance.
Walgreens initially bought a 45 percent stake in Alliance Boots, which runs the United Kingdom's largest pharmacy chain, in 2012 for about $6.7 billion in cash and stock. Analysts expect Walgreens will get added negotiating muscle over supplies like pharmaceuticals from the Alliance Boots deal and another ownership stake it acquired in pharmaceutical wholesaler AmerisourceBergen. But the drugstore chain disappointed investors last August when it also lowered a forecast for earnings it expects after combining with Alliance Boots.
Walgreens also said Thursday that it earned $2.04 billion, or $1.93 per share, in its fiscal second quarter. Earnings, adjusted for one-time gains and costs, were $1.18 per share.
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That topped Wall Street expectations. The average estimate of 14 analysts surveyed by Zacks Investment Research was for earnings of 94 cents per share.
But the drugstore chain's revenue of $26.57 billion fell short of analyst forecasts for $27.73 billion.
Walgreen also announced a forecast for full-year earnings in the range of $3.45 to $3.65 per share.
Analysts expect, on average, earnings of $3.62 per share, according to the data firm FactSet.
Walgreens shares edged up 32 cents to $88 in premarket trading about 90 minutes before the market open. The stock had already climbed about 15 percent so far this year, as of Wednesday.