Wal-Mart has expanded their drug program:

Wal-Mart Stores Inc. is expanding its national $4 generic prescription drug program by about 10 percent, adding drugs for some new conditions.

The world's largest retailer said Thursday it has added drugs covering glaucoma, attention deficit disorder, attention deficit hyperactivity disorder, fungal infections and acne.

Two prescription birth control drugs and one fertility drug were added at $9, reflecting a higher cost that the company said could not be brought down further.
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The increase adds about 30 prescriptions, made up of 14 drugs in various doses, to a list of 331 prescriptions and 143 drug compounds sold under the first phase introduced last year.