Tripping with the kappa opiate receptor.
Over the past few years, a little known and highly unusual psychedelic drug has claimed the interest of drug users and drug scientists alike. Salvia divinorum, a green, leafy plant native to the Mazateca region of Mexico, provides its users with a short but intense hallucinogenic experience. A member of the mint family, it is not among the ornamental garden plants sold under the name Salvia at local nurseries.
The high is unlike that from LSD or psychedelic mushrooms, users say, nor is it anything like the experience of smoking marijuana. Salvia is not currently controlled by federal law, but dozens of states have moved to outlaw cultivation and sale of the plant, which is currently freely available for purchase on the Internet.
As an herb with psychedelic properties, Salvia divinorum is of pharmaceutical interest because of its uncommon affinity for opium/endorphin receptors—specifically the kappa opioid receptor. Most drugs with classical “psychotomimetic” properties, like LSD and MDMA, are highly selective for the 5-HT(2A) serotonin receptor.
Salvia is not one of these. Like ibogaine, another hallucinogenic shrub with a weak affinity for kappa opiate receptors, Salvia’s active ingredient--Salvinorin A--causes psychoactive effects not usually associated with stimulation of the brain’s internal opioid system. Previous research had identified a few such compounds, such as enadoline, which produced similar hallucinogenic effects.
The pharmaceutical industry has already taken a look at the kappa-opioid agonists in the ongoing search for new painkillers, and has so far discovered the usual psychedelic trap of too many unpredictable side effects for a commercial medication.
Classified as an “atypical” psychedelic, the salvia high is intense, dream-like, and short-lived, tapering off after about 30 minutes. An ounce of salvia in leaf form sells for as little as $40, but more concentrated liquid extracts sell for as much as $60 per gram.
Salvia’s addictive potential is low to nonexistent. No hallucinogen such as LSD or peyote has ever been found to be addictive in the classical sense.
Nonetheless, fearing that the inexpensive plant might become “the next marijuana,” as an Associated Press report put it last month, 24 states have passed, or are considering, legislation to restrict access to salvia. Elsewhere, sale of the drug has been restricted in Spain, Italy, Sweden, Belgium, Australia, and other countries. In the AP article, a Florida state legislator alleged—with unintended irony: “As soon as we make one drug illegal, kids start looking around for other drugs they can buy legally. This is just the next one.”
There are many reasons why Salvia divinorum is not likely to be “the next one.” According to drug expert Rick Doblin of the Multidisciplinary Association for Psychedelic Studies (MAPS), salvia “tastes terrible” and is “not going to be extremely popular.” The popular drug information site EROWID describes salvia as “more scary than fun” for many users, concluding that, whether smoked or swallowed, the plant is “aversive for many who try it.” Like ibogaine, salvia is no party drug. It can result in confusion, dizziness, depersonalization, and all the other hallmarks of a “bad trip.”
A related question is the extent to which kappa opioid receptor boosters might reduce the craving for addictive drugs. Ibogaine has been touted for having precisely this effect on heroin addicts and others. However, an early study of kappa opioid receptor-active compounds did not find any reduction in self-administration of cocaine.
The National Institute of Drug Abuse (NIDA) is studying salvia. The Drug Enforcement Administration (DEA), citing salvia as a “drug of concern,” is evaluating it.
Photo Credit: http://www.salvia-divinorum-extract-now.com/
