A tour guide whose body was found in a Whitton pond had drowned after taking a potentially fatal amount of cocaine, an inquest heard.

Adrian Joseph, 33, was found face-down in shallow water in Crane Park’s nature reserve at about 11am on September 16 last year and had a history of cocaine and anabolic steroid abuse.

Mr Joseph, from Hounslow, had also been prescribed anti-depressants following an overdose of prescription drugs in May 2013, West London Coroner’s Court heard on Monday.

This earlier suicide attempt was deemed a "cry for help" by his girlfriend Gemma McCann, and senior coroner Chinyere Inyama said that on this occasion he did not believe for one moment that Mr Joseph intended to take his life.

The toxicology report revealed Mr Joseph had cocaine levels of 1.46mg per litre of blood in his system, and the minimum lethal dose can be anything above 1mg per litre.

Mr Inyama recorded a conclusion of death by misadventure, and said that it was entirely plausible the cocaine had rendered Mr Joseph into an intoxicated state that caused him to drown in water shallow enough for him to stand up in.

Natasha Harris, who was in the park the night before Mr Joseph’s body was found, told the coroner’s court she heard people enter the park at about 11pm.

She called police when she heard a grunting noise and a man’s voice yelling: "Get off me, you’re going to kill me," but when officers arrived that evening they found nothing suspicious.

The pathologist’s report found no compressions on Mr Joseph’s neck and no evidence he had been involved in an assault, and Mr Inyama suggested the voices may have come from Mr Joseph’s laptop.

He said: "If there were people in the park, Mr Joseph had not been one of them."

Mr Joseph’s father described his son as "jovial" and said: "There was nothing to concern me at that time. He would tell me if there was something wrong."

Mr Inyama said the amount of cocaine taken by Mr Joseph would have meant he died very soon after ingestion.