City clubbers are risking their lives by taking "fake" party pills on nights out, experts have warned.
The fake ecstasy scam produces a product so diluted it contains only fraction of the drug - and it is making drug dealers richer than ever.
Benzocaine, used legally as a dental anaesthetic, is made cheaply in China and is easily available for sale on the internet.
Users can still get a "high" if the substance is snorted or injected, so drug suppliers are using it to bulk out ecstasy pills.
A source told the Evening Times: "Dealers use benzocaine to make money.
"They don't care what mixing agents they use, or how dangerous they are, as long as they look like drugs and can create a similar effect.
"You could be putting anything in to your body.
"Although benzocaine is legal, it is an extremely dangerous drug, if not used properly."
China is a leading producer of benzocaine, which has a numbing sensation.
The drug is also used in sunburn remedies.
Police Scotland warned about the dangers of unknown bulking agents.
In a statement, officers said: "Powders and tablets can be mixed with other substances to make it look like you are getting more.
"These mixers are known as adulterants and can be substances such as benzocaine, used by dentists, creatine, used by body builders and caffeine, found in energy drinks.
"In the short term they can affect different people in different ways."
More and more people are going to hospital after taking these substances with specific symptoms such as nose bleeds, bleeding tongues, sickness and diahorrea, black outs, short-term memory loss, panic attacks and severe mood swings."
Detectives previously warned young people, especially clubbers, about Mortal Kombat ecstasy pills.
It followed the death of 17-year-old Regane MacColl who fell ill in Glasgow's Arches nightclub.
She died in the early hours of Sunday, February 2, in the city's Royal Infirmary.
Police believe her death could be linked to red Mortal Kombat ecstasy tablets.
It is understood the deadly pills contain paramethoxyamphetamine (PMA) - a substance that can be five times stronger than ecstasy.
Demand for ecstasy has soared in recent years and is now cheaper and widely available.
Anyone with any information about the distribution or production of illegal drugs is asked to contact Police Scotland on 101.