DEERFIELD, Ill. — Walgreen Co. turned in another same-store sales gain in March, with business up in both the pharmacy and front end.

Walgreen Co. turned in another same-store sales gain in March, with business up in both the pharmacy and front end.

The drug store chain said Monday that sales in comparable stores for the month rose 2.3% year over year, up from a 0.4% uptick in February, when the company ended two straight months of same-store declines.

Walgreens noted that calendar day shifts had a positive impact of 1.1 percentage points on same-store sales in March, which had one more Wednesday and one less Sunday versus a year earlier. Comparable-store sales also were helped by 0.7 percentage points due to an earlier Easter this year, the company said.

In the pharmacy, same-store sales climbed 2.4% in March, reflecting a 1.7 percentage point positive impact from calendar day shifts and a 2.6 percentage point negative impact from generic drug introductions in the last 12 months as well as a lower incidence of flu versus a year ago, Walgreens said.

Prescriptions filled at comparable stores increased 4.5% in March, including a 1.5 percentage point gain due to more patients filling 90-day prescriptions, according to the company. Calendar day shifts positively impacted prescriptions filled in comparable stores by 1.6 percentage points.

In the front end, same-store sales rose 2.2% in March, helped by a 2.1 percentage point positive impact from this year’s earlier Easter, the retailer reported.

Walgreens’ overall March sales came in at $5.82 billion, up 6.4% from $5.47 billion a year earlier. Total pharmacy sales gained 5.6% during the month, while front-end sales climbed 6.6%.

For the calendar year to date, revenue increased 4% to $16.47 billion from $15.83 billion in the year-ago period. Fiscal 2010 sales for the first seven months were $39.17 billion, up 6.2% from $36.89 billion in the prior-year span.

Walgreens said it opened 52 stores during March, including eight relocations, and acquired four stores and closed three units. As of March 31, the retailer operated 7,225 drug stores, up 489 from a year ago, including 63 stores acquired over the last 12 months.