Kmart said Wednesday it has expanded its discount drug program to include 70 new medications, including generic versions of the popular anti-depressant Zoloft and cholesterol fighter Zocor. 

Under the program launched in May, 2006, customers of Kmart's 1,100 pharmacies can get a 90-day supply of generic versions of more than 300 medications for $15. 

Among the new drugs being offered is the anti-depressant sertraline, a generic version of Pfizer’s Zoloft, and generic simvastatin, a derivative of Merck’s cholesterol drug Zocor. Neither of these products is currently offered by competitors Wal-Mart Stores Inc. or Target Corp., according to their Web sites.

Kmart is the only discount retailer to offer a 90-day drug program.  Wal-Mart and Target both offer 30-day discount programs with drugs priced at $4. Wal-Mart offers over 300 drugs in all of its 3,810 U.S. pharmacies.

“Our program is very robust and we have the medications that are frequently prescribed to our customers,” said Kmart spokeswoman KirstenWhipple.

The announcement comes one day after Kmart's parent, Sears Holding Corp., warned of lower second quarter earnings. 

Whipple would not comment on whether the expanded drug program is expected to boost lagging sales, but she said that by attracting more customers to Kmart's pharmacy, the program offers more opportunities for sales of other products throughout the store.

Convenience-based pharmaceutical suppliers like Deerfield, Ill.-based Walgreen Co. and Providence, R.I.-based CVS Caremark Corp. do not offer generic drug programs, but analysts do not think this will affect their bottom lines.

In fact, said Derek Leckow, an analyst at Barrington Research, such discount drug programs have yet to adversely impact the major drugstore chains.

“With these programs in Kmart, and Wal-Mart, we have seen very little change in same-store sales [at Walgreens].” Leckow said.

Leckov said Walgreens customers usually have insurance coverage for their prescriptions, rather than paying out-of-pocket as Kmart customers do.

“Walgreens to a large extent offers the same discount that these other programs offer,” Leckov said. “Through third-party payers, the customers end up paying about the same.”

In addition, Leckov said, the major drug chains have more, and more convenient locations throughout the city and suburbs.  By contrast,  Kmart and Wal-Mart have fewer mega stores in more remote areas..

“When it comes to convenience, are they going to spend more money on gasoline by driving out to these locations?” Leckow asked.

Shares of Sears Holdings Inc. rose 75 cents per share to close at $154.96.