Sarah O'Dowd, 24, lost consciousness and slipped under the water after taking the liquid drug along with ketamine – a powerful horse tranquiliser.

An inquest heard how Mrs O'Dowd died in the Leeds home from where she operated a business selling a drug similar to GHB.

The couple were involved in the manufacture and mail order selling of GBL (Gamma Butyrolactone), a substance which has a similar effect to GHB (gamma hydroxybutyric acid)

It can produce a euphoric high but too much can cause nausea and unconsciousness.

Leeds Coroner's Court heard how husband Liam tried to revive his wife after being woken by the sound of the bath overflowing at their home on Holt Park Crescent, Holt Park.

He was initially arrested on suspicion of murder, but no charges were brought against him.

Deputy Assistant Coroner Richard Manners said: "GHB has been called quite recently the date rape drug. It is a drug, which if administered in small quantities can make someone reasonably happy, but in large quantities can induce a deep coma and in the wrong hands can cause someone to be oblivious as to what is happening.

"It appears that Mr and Mrs O'Dowd had an interesting business involved in the manufacture of drug GBL which is a source of the drug that was actually found in the lady's body and they acknowledged that they had both used it in the past."

The court heard how Mrs O'Dowd had used the drug as she was having trouble sleeping due to health problems.

The couple, both former Leeds University students, had been together for five years and had been married five months.

A statement from a friend, David Docherty, described how Mrs O'Dowd was a regular user of recreational drugs, including cocaine, ecstasy, GHB and ketamine.

Mr Docherty described how Mrs O'Dowd, who had the nickname Zipper, often drank heavily and was capable of drinking a full bottle of spirits on a night.

He added: "It appeared she took drugs at all times of the day."

Pathologist Christopher Milroy gave the cause of death as drowning in association with taking GHB.

Mr Manners recorded an open verdict.

He said: "I cannot say with certainty that she died from the drugs which she had taken or whether she had intended to cause her own death. It seems to me that she was newly married and had everything to live for.

"I can only think the combination of the drugs was probably the likely cause of her falling asleep and slipping under the water."

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