A MAN accused of murdering his friend had between 10 and 30 times the safe dosage of a drug which can cause delirium and confusion in his bloodstream, a court was told yesterday.

Forensic toxicologist Jane Officer told the High Court in Glasgow that William Cameron, 39, had taken the drug Etizolam – which is banned in the UK – along with Diazepam and alcohol.

Ms Officer was giving evidence at the trial of Cameron, of Hollows Avenue, Paisley, who denies murdering 43-year-old Darryl Fitch during a camping weekend at the Locher Water, near Bridge of Weir, between July 10 and 13, 2015.

It is alleged that Cameron repeatedly inflicted blunt force trauma to Mr Fitch’s head by striking him with a blunt instrument or against a hard surface, causing him to fall and drown.

Ms Officer told prosecutor Richard Goddard that side effects of Etizolam, which is not prescribed in the UK, include drowsiness and disorientation and symptoms include confusion and delirium if too much is taken.

Mr Goddard asked her: “Is it sold on the black market?”

She replied: “Yes.”

The prosecutor then said: “William Cameron had anything from 10 to 30 times the therapeutic amount of Etizolam. This is well within the toxic level where symptoms include delirium.”

Ms Officer replied: “That’s correct.”

She added that the symptoms could be exacerbated by alcohol and Diazepam.

The sample from Cameron was taken on July 13, 2015, hours after he was found with a spiral fracture to his right leg and Mr Fitch’s body was discovered lying face down in the nearby river.

Forensic toxicologist Dr Fiona Wylie told the court Etizolam can also cause amnesia.

Mr Goddard asked her: “The drug could cause you to go into a mentally disturbed state and afterwards have no memory of what you have done?”

Dr Wylie replied: “Yes.”

Earlier, pathologist Dr Marjorie Turner agreed with defence QC John Scullion that Mr Fitch could have died from an accidental fall from a height into water and then hit his head on rocks.

However, she added: “While I can’t exclude it, it would need to be the most unusual sequence of events.”

The trial before judge Lord Mulholland continues.