The federal government alleges Cardinal Health Inc. and CVS Caremark Corp. were aware of high-volume orders of prescription painkiller oxycodone shipped to two pharmacies in Florida, in a closely watched case probing how much responsibility companies bear for a growing drug-abuse problem.

The allegations were made in written declarations filed in federal court earlier this month by the Drug Enforcement Administration. The declarations allege that drug distributor Cardinal repeatedly overlooked escalating oxycodone orders placed by the two Central Florida pharmacies.