Clinical Textbook of Addictive Disorders 3rd ed - R. Frances, S. Miller, A. Mack (Guilford, 2005) WW

260 IV. SPECIAL POPULATIONSneous use of intravenous heroin and cocaine (“speedball”) does not result in anovel set of experiences, nor does it reinforce the effects of either drug whenused alone, especially when cocaine and heroin are used in high doses.Cocaine, however, has been shown to alleviate some symptoms of opioid withdrawal,and as such may be used in a self-medicating pattern, as mentioned earlier(Leri, Bruneau, & Stewart, 2003).CannabisCannabis use among patients in methadone treatment programs has recentlybeen investigated in an attempt to answer the practical question of whethercannabinoid-positive urine toxicology examinations predict poor treatmentoutcome. Both a recent Israeli study (Weizman, Gelkopf, Melamed, Adelson,& Bleich, 2004) and a review of three U.S. studies (Epstein & Preston, 2003)suggest that cannabis use is not a risk factor for treatment outcome ofmethadone-maintained outpatients. The authors concluded that cannabinoidpositiveurines do not need to be a major focus of clinical attention.OverdoseIn examining both fatal and nonfatal heroin overdoses, the majority of casesinvolve simultaneous use of alcohol, benzodiazepines, and tricyclic antidepressants(TCAs), such that the toxicology of heroin overdose is probably bestdescribed as “polydrug toxicity” (Darke & Hall, 2003; Darke & Zador, 1996). Infatal heroin overdoses, alcohol has been used more than 50% of the time(Darke & Hall, 2003). The mechanism of action for the overdose appears to bethe synergistic effect of the various depressants on the central nervous system,leading to respiratory collapse. This is further collaborated by autopsy findingsof an inverse relationship between alcohol and morphine blood concentrations;in the presence of alcohol, lower levels of morphine are sufficient to result indeath (Darke & Hall, 2003). In a study by Darke and Ross (2000) in Sydney,Australia, both fatal and nonfatal heroin overdoses were linked to concomitantuse of TCAs but not selective serotonin reuptake inhibitors (SSRIs), despitethe fact that heroin users in Australia predominantly use SSRIs instead ofTCAs.Adolescents, Club Drugs, and the Rave SceneA recent review of the literature revealed that club drug use [MDMA (3,4-methylenedioxymethamphetamine), ketamine, and GHB (gamma-hydroxybutyricacid)] has reached epidemic proportions and is particularly problematicamong adolescents with psychiatric illness, including mood and anxiety disor-