The Independent Police Complaints Commission (IPCC) issued its findings from an investigation into the death of 19-year-old Reece Staples while in police custody back in 2009.
The investigation was completed in 2010, but publication of the findings was delayed until the outcome of an inquest.
On Monday a jury at Notts Coroner’s Court returned a verdict of death by misadventure.
The IPCC said officers should have taken him to hospital for treatment straight away after he said he had swallowed drugs.
At 1.15 am on 7th June 2009 Mr Staples was arrested in Mill Street, Nottingham on suspicion of criminal damage.
He told officers a number of times he had ‘been to Costa Rica three days ago and swallowed some coke’ adding, ‘I’m going to die’.
He was taken to Oxclose Lane Police Station and put in a holding room where he was seen to act strangely.
He remained in a cell until shortly before 5am when CCTV showed him have a seizure and collapse. He was taken by ambulance to the Queens Medical Centre where he died.
A post mortem found Mr Staples died of cocaine toxicity after 19 packages of cocaine were found in his stomach.
A forensic pathologist told the inquest Mr Staples would have died even if he had been taken to hospital earlier.
Notts Police have made a number of changes to custody training and practice to address the findings of the investigation and have reinforced that if an individual is believed to have swallowed drugs they must be taken to hospital.