It was in March last year that the man became acutely ill at home and the condition was life-threatening when the ambulance arrived at the scene.
The man survived after intensive care in hospital.
No medical staff understood what the cause of the condition was, but the man claimed that the co-worker tried to murder him.
First, the police got stuck in the technical examination of the man's physical condition.
But after contacting a medical expert on poisoning, the investigation came loose. Hair samples from the man were submitted for analysis to find out if there were any traces of potentially toxic substances.
- We were then struck that there were traces in the hair of the net drug 3-fluoroethamphetamine (3-FEA). It is a psychoactive substance that is now classified as a drug. The analysis message was a breakthrough in the investigation, explains Lena Samuelsson, investigator at the section for serious crimes in Greater Gothenburg, in a press release from the police.
Before the cohabitation got the seizures, he stated to the police that the cohabitation had given him a fluid which she claimed was a cholera vaccine.
Now the man's cohabiting partner is being prosecuted. She has been remanded in custody since May this year on probable grounds for murder.
The 44-year-old woman denies the crime.