The state attorney general's office charged Phillip A. Henkel, 60, of Millersville, with two felony drug charges and one count of felony theft.
Prosecutors said Henkel gave away about $3,000 worth of drugs and took drugs for himself, and that he stole other things from the Weis Markets store in the town of Willow Street, including cash and merchandise.
"Henkel advised while working at Weis he was a loose cannon," wrote William J. Delgado, an investigator with the attorney general's office, in a court affidavit. "Henkel stated besides diverting medications for him and friends, he stole money from the cash register or pocketed customers' co-pays."
Delgado said Henkel also admitted to pocketing money rather than ring up minor sales, and to stealing groceries.
Reached at his home for comment, Henkel said "don't believe everything you hear," then hung up on a reporter.
The arrest affidavit said a store audit found nearly 38,000 pills were missing.
Henkel faces charges of theft by unlawful taking, illegal dispensing of controlled substances and obtaining controlled substances by misrepresentation, fraud, forgery, deception or subterfuge.