KETAMINE, a powerful animal anaesthetic also known as Special K, cat valium and LA coke, is the latest drug to appear on the streets in the Republic.
Gardai have made some 30 seizures in the past 12 months of tablets containing the hallucinatory substance, which has swept the New York rave scene.
But the drug which causes "out of body" experiences and is fast becoming the choice of Britain's so called "chemical generation" is not being sold in its pure form in the Republic.
Instead, it is mixed with the drug ephedrine and passed off in tablet form as ecstasy, the street name for hallucinogenic amphetamines.
Sgt Gearoid Begley, the head of Tallaght district drugs unit, said it seemed the tablets were being sold to unwitting buyers who believe they are purchasing "real" ecstasy.
Tablets containing ketamine and ephedrine were seized in Tallaght over the past five months.
"The tablets have the appearance of E. They are white or yellow with a dove stamp," said Sgt Begley.
"We haven't heard of people deliberately selling ketamine on its own yet. My suspicion is that the people who are using the tablets think they are E. Whether they have a different effect on them, we don't know," he said.
The side effects of ketamine when taken orally include confusion, hallucinations and irrational behaviour, according to Dr Jim Donovan, director of the Forensic Science Laboratory.
"The blood pressure and heart rates would also be increased. Ketamine varies the beat of the heart and if there was any murmur or irregularity in the beat it would increase enormously. If taken on its own, respiration will be depressed and nausea and vomiting can occur. Ephedrine also increases the pace of the heart."
For ecstasy users, the emergence of tablets containing ketamine and ephedrine is potentially dangerous as 5 to 20 per cent of people are "particularly susceptible" to the ill effects of the ketamine, according to Dr Donovan.
He said the exact effect of these two substances combined is not yet known.
"From our knowledge, the combination of something like ephedrine with ketamine is bound to affect the lungs and the heart rate.
"By definition, something which gives hallucinations has the potential to affect weak spots of your body. This is why young people who have taken ecstasy die from heart attacks or strokes when dancing. That is because ecstasy affects the rhythm of the heart, just like ketamine," he said.
In Britain, anecdotes about ketamine in impure ecstasy tablets which have circulated the club scene include incidents of ravers suddenly losing the power of speech or becoming unable to move their limbs.
According to Dr Donovan, there have been about 30 seizures of tablets containing ketamine in the State in the past 12 months, mostly in Dublin.
The quantities have ranged from a few tablets to several dozen.
Ketamine is not a controlled drug in the Republic and therefore is not illegal. But when mixed in tablet form with ephedrine, which was made illegal in 1993, the tablet is illegal.
Ketamine in its pure form is a liquid which is normally baked into crystals, ground into a powder and then snorted.
Ketamine is most commonly used by vets as an animal anaesthetic and is sometimes used as a human anaesthetic.
Unlike with other anaesthetics, patients remain conscious. Dr Donovan says a Swedish colleague who was recently given a ketamine injection while undergoing surgery on his hip told him he sensed that "his mind was leaving his body and going around the room".