The drug has been used to spike drinks in pubs and clubs

Denise Macpherson, 45, and Hanan Rabin, 53, are charged with exporting a derivative of GHB to the US.

They are also accused of supplying the drug from an address in West Lothian.

A Hebrew interpreter will have to be found to continue the case against Mr Rabin on Friday. Ms Macpherson was granted bail.

They were arrested on Wednesday following an operation led by investigators from the Scottish Crime and Drug Enforcement Agency (SCDEA).

Raids took place on Ms Macpherson's home in Chestnut Grove, Livingston, and at the Eucal Business Centre on Craigshill Road.

We have seen GHB and Rohypnol in fairly small quantities in Edinburgh before but never anything like this Tom Wood Scottish Association of Alcohol and Drug Action

Ms Macpherson and Mr Rabin, of St Peter's Place, Edinburgh, appeared in private at Linlithgow Sheriff Court.

Both are charged with exporting GBL (gamma-butyro lactone) to the US between 19 April and 24 May 24.

They are also accused of supplying the substance from her home between the same dates.

Ms Macpherson is also charged with the possession of cannabis.

Dance culture

GBL is used to make GHB and is often sold by itself. It is orally ingested and turns into GHB in the body, having the same effect.

Also known as liquid ecstasy, GHB is an odourless, colourless liquid sedative which became popular in dance culture.

The drug seized was a derivative of GHB

It is is a powerful anaesthetic which effectively "knocks out" victims and leaves them with no recollection of what has happened.

The Home Office made GHB illegal in 2003, reclassifying it to Class C status.

Possession of the drug without a medical prescription is punishable by a prison sentence of up to two years, while supplying the drug carries a maximum penalty of five years in jail.

Clubbers also use the substance to create a feeling of euphoria as in small quantities it acts as an anti-depressant.

Major operation

Tom Wood, chairman of the Scottish Association of Alcohol and Drug Action, said it was a "very significant" recovery of "GHB".

He said: "We have seen GHB and Rohypnol in fairly small quantities in Edinburgh before but never anything like this.

"It has clearly been a major operation and sounds to me like it was intelligence-led.

"It is very concerning to find such a haul because it shows the quantity of drugs in circulation."

Graham Rhodes, of the Roofie Foundation, which runs a helpline for victims of drug rape, said: "This is not an urban myth, we get 800 to 900 new victims calling us every year."