It was in mid-October that an employee at a nursing home in Nyköping is suspected of having taken the medicine from a user's medicine cabinet.
This is to give it to another employee, who was not on duty at the time.
The medicine was reportedly to be used for the non-employed employee's acutely ill dog.
It was a third employee who became aware of the incident and reported it.
According to the municipality's internal investigation, the drug must have been classified as a drug.
The investigation also shows that the resident was allowed to be without his medicine, which must be taken if necessary, for twelve hours.
The resident was thus exposed to risk that could have had serious consequences, according to the municipality.
The incident is now reported to the Swedish Health and Care Inspectorate, Ivo.