A headline-making prescription discount program has holes.

The National Community Pharmacists Association, Alexandria, Va., is making that argument in a critique of the “$4 prescription” sale recently introduced by Wal-Mart Stores Inc., Bentonville, Ark.

Wal-Mart’s $4 drug list includes only 300 of the 11,000 drugs available in the United States, and the true number is closer to 150, because the list includes multiple versions of some drugs, such as 12 different versions of the antibiotic amoxicillin, the NCPA contends.

Moreover, many of the medications are older medications that are less effective than or have more side effects than the newer drugs, the NCPA says.

The original Wal-Mart list excluded all generic statins – drugs used to treat high cholesterol – and the generic statin now included is an older drug that tends to be less effective than other statins, the NCPA says.

The NCPA adds that it is “examining any anti-competitive aspects of Wal-Mart’s action” to set up the $4 drug program.