Use of the so-called "dappou herb," a street drug typically produced by mixing herbs with synthetic cannabinoid (estimated to be the pharmacologically effective ingredient), has recently spread to young people in Japan who consider it a new recreational drug. It is not legally regulated because no illicit ingredients have been detected in the drug by conventional screening tests. It is easily obtained via the Internet or from street vendors. As the population abusing this drug has grown, medical problems such as psychosis, disturbances of consciousness caused by acute intoxication, and social problems such as traffic accidents while under the influence of the drug have been increasingly reported. However, few psychiatric symptoms associated with it have been identified, and little is known about the psychosocial features of abusers. The purpose of the present study was to examine the clinical and psychosocial features of outpatients with dappou herb use disorder.
Subjects were 15 male outpatients with dappou herb use disorder who had their first medical examination at the Drug Dependence Clinic in the Center Hospital, National Center of Neurology and Psychiatry between November 2009 and April 2012. The control group comprised 28 age-matched oupatients who had methamphetamine use disorder, the most serious drug-related problem in Japan since the 1950s. They underwent their first medical examination at the same clinic during the same time frame as the study subjects. Clinical and psychosocial information on subjects and controls including life histories (educational, occupational, and criminal) and clinical information (history of psychoactive substance use, access to the mainly abused drug, and DSM-IV diagnoses of substance use disorder and comorbid psychiatric disorders) were collected from medical records. These variables were compared between the two groups.
Analyses revealed differences in the life history and clinical characteristics between the subjects and controls. The subjects had a higher level of education, more work experience, and a less marked history of anti-social behavior other than illicit drug use and possession than the controls. However, a clinical history of psychiatric disorders, other than substance-related disorders, before drug abuse began was more frequently found in the subjects than in the controls.
The present study demonstrates that patients with dappou herb use disorder may differ from those with methamphetamine use disorder in terms of their background, psychosocial factors, and clinical features. These findings suggest that the dappou herb may be creating a new type of drug abuser in Japan. Our study also indicates that some patients abusing this herb may have been "self-medicating" for symptoms of other psychiatric disorders such as depression or anxiety, given that they were more likely to have received psychiatric treatment before the start of drug abuse. This suggests that the legal regulation of this drug as well as early comprehensive intervention for adolescents with mental health problems may be required to prevent abuse of the dappou herb. Two limitations of this study should be noted. The definition of the dappou herb was vague because the ingredients are still unclear. In addition, the sample size of this study was very small. However, no studies using larger samples have been reported in Japan. Future studies that overcome these limitations are needed.