The lawsuit involves the "off-label" uses of the anti-psychotic drug Zyprexa, the Jackson (Miss.) Clarion Ledger reported.
The suit alleges representatives of Eli Lilly persuaded Mississippi doctors to prescribe the drug to patients suffering from conditions such as anxiety, mood swings and disturbed sleep when the drug is only approved to treat bipolar disorder and schizophrenia.
Tim Balducci, Mississippi special assistant attorney general, told the Clarion Ledger Eli Lilly targeted Mississippi because the state's Medicaid system cannot determine when a medication is prescribed for non-approved uses.
The Indianapolis-based Eli Lilly has 30 days to respond to the suit.