CHICAGO (

TheStreet

) --

Walgreen

(WAG)

might be suffering from some type of seasonal sales bug, as the company announced that its same-store sales rose just 1.9% in August, missing analysts' forecasts.

While pharmacy sales at stores opened at least a year grew 3.8%, front-end comparable sales, which include hair-care products, cosmetics and other discretionary items, slipped 1.3%.

Two analysts polled by Thomson Reuters expected same-store sales to jump 3.1%.

Prescription same-store sales rose 4.8%. Pharmacy sales accounted for 66% of total sales for the month.

Earlier this week Walgreen, along with its drugstore rivals

CVS Caremark

(CVS) - Get Report

and

Rite Aid

(RAD) - Get Report

, began offering

flu shots

.

Any bump from those initiatives would not be reflected in the company's August sales figures, although swine flu fears are ultimately expected to increase the number of customers looking to protect themselves this fall.

-- Reported by Jeanine Poggi in New York

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