A man with a history of drug abuse was found dead on his sofa by his son, an inquest heard.

Paul Colls was 44 when his son Wayne found him in the living room of his home in The Ridge, Shirehampton on May 18, 2007.

An inquest at Flax Bourton Coroner's Court heard that Mr Colls, also known as Paul Chapman, had suffered a bout of pneumonia earlier in the year, but had continued to smoke several roll-up cigarettes every day.

He smoked cannabis regularly, occasionally took heroin and the post-mortem examination report confirmed the presence of morphine in his blood – which indicated that he may have taken heroin on the day he died.

Mr Colls, who had been diagnosed with paranoid schizophrenia at a young age, was also found to have several types of medication in his blood, as well as methadone.

The post-mortem examination also showed evidence of emphysema and fluid in his lungs.

In a statement read out by the deputy assistant coroner Terry Moore, Mr Colls' sister Mandy said he had called her a few days before he died to say he did not feel well and did not have long to live.

Mr Colls also told a friend the night before he died he thought he was going to die.

The police constable who attended Mr Colls' home when his body was found said his son Wayne had refused to leave his side and was "extremely upset".

Mr Moore said he was convinced the drugs in Mr Colls' blood, along with his health conditions, were "more than enough to kill him".

Recording a verdict of misadventure, he said: "This is not a normal drug death. This is someone who has used drugs at the wrong point in time, when they have been very vulnerable – and it has killed them."

Mr Colls' two sisters, Mandy and Julie, attended the inquest and appealed afterwards for his two sons to get in touch. Mandy Colls, 42, of Yeovil, said: "He had two sons, Wayne and Ady, who would be about 24 and 20 now. We think they live in Southmead, but I haven't heard from them for two years.

"Please get in touch, even if it's just to say you are safe – I promised Paul I would look after you.

"Paul was a lovely man, and he will always be missed."

To contact Mandy, call 07591 867767.