SAN DIEGO - The illegal designer drug known as "bath salts" could be more addictive than methamphetamine, researchers at The Scripps Research Institute in La Jolla announced Wednesday.
The drug, officially known as 3,4-methylenedioxypyrovalerone, or MDPV, is a derivative of cathinone, the principal active ingredient in khat, a leaf chewed for its stimulant effects throughout northeast Africa and the Arabian peninsula.
"We observed that rats will press a lever more often to get a single infusion of MPDV than they will for meth, across a fairly wide dose range," said TSRI associate professor Michael Taffe, the principal investigator of the study.
TSRI associate professor Tobin Dickerson and Taffe began looking into so-called designer bath salt drugs when they started becoming popular in the United Kingdom.
"Animals were doing strange things like licking the sides of their cages," Dickerson said.
Nancy Knott with the Scripps Treatment program in La Jolla said that is one of the key signs of bath salt use in humans.
"Picking of the face, constant licking, erratic and violent behavior are all signs of bath salt use," she said.
TSRI said its study, one of the first laboratory tests of bath salts, was published online by the journal Neuropharmacology, and will appear in the print publication next month.
"When we increased how many lever presses a rat would have to emit to get an additional infusion of drug, we observed that rats emitted about 60 presses on average for a dose of meth but up to about 600 for MDPV -- some rats would even emit 3,000 lever presses for a single hit of MDPV," said TSRI research associate Shawn Aarde, the first author of the study. "If you consider these lever presses a measure of how much a rat will work to get a drug infusion, then these rats worked more than 10 times harder to get MDPV."
The sale of MDPV is prohibited in the U.S., Canada and U.K. Taffe said variants of the drug are being created to get around the regulations, and they will also have to be studied.
According to the researchers, cathinone derivatives inhibit the normal removal of neurotransmitters like dopamine, noradrenaline and serotonin. This results in disturbances in areas of the brain that mediate desire, pleasure, muscle movements and cognition, they said.
Users feel an initial euphoria, increased physical activity, an inability to sleep and a lack of desire for food or water, along with almost irresistible cravings to take more of the drug, according to TSRI.
They said higher doses bring a strong risk of paranoid psychoses, violence and suicide.
Though banned, bath salt use is still prevalent, which is why the research continues.
"What we want to do is develop a vaccine, it's what we do for drug treatment at the Institute, but we also want to figure out how to prevent people from getting hooked in the first place," Taffe said.