The coroner has ruled that a Whanganui electrician found dead with syringes beside him and a glass pipe in his hand died from an accidental overdose.
Paul Haydon Alexander Cook was found dead in a bedroom at his parents' house in Whanganui about 5pm on April 2, 2016.
The direct cause of his death was multiple drug toxicity - the two drugs in his system were the opioid Fentanyl which is 50 to 100 times more potent than morphine, and Notriptyline.
Around eight years before his death, the 24-year-old suffered a shoulder injury in a quad bike accident.
Two and a half years later he aggravated his injury and underwent surgery, but remained in constant pain. His doctors were never able to diagnose the cause or treat it with anything other than pain medication.
Paul's mother, Tina, said he suffered multiple overdoses in the last two and a half years of his life.
She said in the last six months of his life these became a lot worse, and Paul denied he had an addiction problem.
Police contacted Paul's parents, Tina and Bruce, on March 30 and said Paul had had a further collapse.
Constable Brett Humphrey, of Whanganui police, asked if Tina and Bruce would be willing to have Paul living at home with them for the immediate future.
Tina last saw Paul at 10.30pm on Friday, April 1, when she said everything appeared to be normal.
The next morning Tina and Bruce went about their morning and headed into Whanganui to undertake work on a rental property they own.
When they returned at 5pm, Tina knocked on Paul's bedroom door and entered the room to find him lying in an unnatural position on the floor.
Paul had a glass pipe in one of his hands and a piece of tinfoil in the other.
There were three syringes and a needles on the bed next to the pillow and a medicine box containing strong pain medication.
Police said it looked as if he had been smoking a drug of some sort and collapsed.
After the post-mortem, Dr Kate White concluded the cause of Cook's death was multiple drug toxicity, as a result of intravenous injection of Fentanyl while Paul was also using transdermal patches containing Fentanyl.
Coroner Tim Scott ruled that it was unlikely Paul overdosed to commit suicide, instead he believed the most probable reason for him using the drugs was as self-administered pain relief.
Mr Scott wrote that it did not particularly surprise him that Paul Cook may have unintentionally overdosed.
"Many people are comfortable to exceed recommended dosages of a drug in the hope that this will give them the pain relief they seek when the recommended dosage will not," he said.
"This is what I think Paul did. He basically took far more by quantum than the dosage that was recommended in the hope and expectation it would grant him pain relief. He did not intend the consequence that actually occurred - death."