A new audit claims Missouri owes the federal government $34 million for not complying with Medicaid regulations.
A U.S. Department of Health and Human Services audit set for release Tuesday shows Missouri didn't bill drug manufacturers for rebates.
The St. Louis Post-Dispatch reports that meant drug companies kept more money while there was less for Medicaid recipients.
The Missouri Department of Social Services oversees the program and says it disagrees with the audit.
A department spokeswoman says the amount owed is closer to $7 million.
States are supposed to collect rebates for medication given at hospitals by submitting drug data to manufacturers.
But the audit shows Missouri failed to do that for at least three years. State officials have said financial and administrative barriers made compliance challenging.