A onetime Twin Cities pharmacist has been charged with stealing roughly 20,000 doses of addictive drugs over several years from his workplace, the Hennepin County Attorney's Office announced Monday.

Jeffrey F. Grothaus, 49, will appear Tuesday in district court on four counts of theft by swindle, alleging he stole the pills from two Park Nicollet stores: Carlson Pharmacy on Twelve Oaks Center Drive in Minnetonka and Wayzata Pharmacy on North Central Avenue in Wayzata.

Grothaus, of Maple Grove, was charged by summons and has not been taken into custody. His attorney declined Monday to comment.

"The opioid crisis has opened everyone's eyes to the abuse of prescription medications," County Attorney Mike Freeman said in a statement. "While Mr. Grothaus says he used the stolen pills for his own addiction, we cannot have these powerful drugs leaking out into the community, which is why we are prosecuting a pharmacist."

Grothaus is accused of stealing five types of drugs, mostly the sedative zolpidem (sold under the brand name Ambien) and the opioid painkiller tramadol (brand name Ultram).

According to the criminal complaint:

An internal investigation by HealthPartners at the two Park Nicollet pharmacies in July 2016 found unusually large adjustments to the stores' inventory.

On June 15, 2016, for example, an adjustment for 500 tablets of Zolpidem was entered into the computer at the Wayzata pharmacy. However, a search of all HealthPartners/Park Nicollet pharmacies failed to show those 500 pills turning up somewhere else.

The adjustment was made at a pharmacy technician's computer station. However, store video showed Grothaus at that station. Video also showed Grothaus taking an item, slipping it into his pocket, then removing it from his pocket and putting it in his work locker.

Five months later, Grothaus admitted in writing that he began stealing drugs in June or July of 2012.

A Health Partners spokeswoman said Monday that Grothaus no long works for Park Nicollet. "We monitor medication dispensing and disposal, and work to eliminate opportunities for drug diversion by addressing structural or root causes," said spokeswoman Erin Ghere.

Paul Walsh • 612-673-4482