An inmate found dead within hours of arriving at Winchester Prison died of natural causes as a result of pneumonia, an inquest has ruled.

Jurors agreed that an overdose of the prescribed anti-depressant, venlafaxine, as well as coronary fibrosis were probably contributory factors to the death of John Terrain (50), formerly of Barnes Close, Bitterne, Southampton.

But his unhappy family say they will take High Court action against the jail alleging negligence.

Daughter, Lily Terrain, said: "We are not going to give up on this. We are going to take this further until we get justice."

Mr Terrain, who was a diabetic and was suffering from a chronic chest infection, died in the jail's health care centre on September 7th last year, shortly after being sentenced to three years imprisonment for drug offences.

During the course of the three-day hearing, the inquest heard that Mr Terrain had collapsed on his way to the health care centre and was found to have a pulse rate of 120 beats a minute, but was not seen by a doctor.

A nurse who assessed him on his arrival at the jail said he was so angry and agitated that she was unable to take his blood pressure or pulse properly.

The inquest heard that Mr Terrain, who also suffered from depression and anxiety, was on a large amount of prescribed medicines as well as antibiotics for his chest infection and insulin for diabetes.

A post-mortem examination revealed high levels of venlafaxine and chlorpromazine above the therapeutic levels, which suggested a possible overdose.

But coroner, Grahame Short, stressed that there was no evidence that Mr Terrain had taken an excessive amount of the drugs deliberately.

He had the medicines in his possession until he was taken into custody by Premier Prison Services after he was sentenced and therefore had an opportunity to take the drugs prior to his arrival at the jail.

Summing up, Mr Short emphasised that Mr Terrain's general state of health was not good and said he believed he was put under even more stress because of the pending court case.

He also explained that according to the evidence the pneumonia was the result of a combination of factors which made Mr Terrain particularly vulnerable, including the chest infection, the diabetes and coronary fibrosis.

But after the inquest his daughter said the whole family were disappointed and upset by the outcome. "We are going to take this further in the High Court because we believe our dad was neglected at the prison," she added.

"He had collapsed and a doctor did not see him. We phoned the prison ourselves that day and told them that our dad was not a well man and he needed to be looked after.

"He should have been taken to the hospital when he collapsed. After all, the hospital is just across the road from the jail."