title: No evidence for reduction of opioid-withdrawal symptoms by cannabis smoking during a methadone dose taper.
abstract: OBJECTIVE
  To support medication development with cannabinoids, smoked cannabis has been said to alleviate symptoms of opioid withdrawal. We evaluated that hypothesis.
  
  
  METHODS
  We analyzed data from the methadone-taper phase of a clinical trial we had conducted. Participants were 116 outpatient heroin and cocaine users (of whom 46 were also cannabis users) who stayed for the 10-week taper. Main outcome measures were weekly urine screens for cannabinoids, plus every-two-week assessments of opioid-withdrawal symptoms.
  
  
  RESULTS
  Opioid-withdrawal scores did not differ overall between users and nonusers of cannabis. In a lagged analysis in the 46 users, there was a slight (not statistically significant) indication that weeks of higher opiate-withdrawal symptoms preceded weeks of cannabis use (effect-size r = .20, 95% CI -.10 to .46, p = .52). Even if this finding is taken to suggest self-medication with cannabis, a lagged analysis in the other temporal direction showed no indication that cannabis use predicted lower opiate-withdrawal symptoms the next week (effect-size r = .01, 95% CI -.28 to .30, p = .69). These findings persisted in sensitivity analyses controlling for each of 17 potential confounds.
  
  
  CONCLUSIONS
  With our findings, the clinical evidence for smoked cannabis as a reducer of opioid-withdrawal symptoms moves slightly further from "inconclusive" or "mixed" and closer to negative, at least in the context of a methadone dose taper like the one used here.
  
  
  CONCLUSIONS
  This finding may remove one rationale for medication development using cannabinoids to treat opioid withdrawal, but leaves other rationales intact.
authors.affiliation: Treatment Section, Clinical Pharmacology & Therapeutics Branch, Intramural Research Branch of the National Institute on Drug Abuse, Baltimore, Maryland.
authors.forename: David H
authors.initials: DH
authors.lastname: Epstein
authors.forename: Kenzie L
authors.initials: KL
authors.lastname: Preston
mesh_terms: D000328:Adult; D019970:Cocaine-Related Disorders / Q000534:rehabilitation*; D004305:Dose-Response Relationship, Drug; D004359:Drug Therapy, Combination; D005260:Female; D006556:Heroin Dependence / Q000534:rehabilitation*; D006801:Humans; D008297:Male; D064086:Medical Marijuana; D008691:Methadone / Q000008:administration & dosage* / Q000009:adverse effects; D008875:Middle Aged; D009294:Narcotics / Q000009:adverse effects*; D013375:Substance Withdrawal Syndrome / Q000534:rehabilitation*; D055815:Young Adult
chemical_list: D064086:Medical Marijuana; D009294:Narcotics; D008691:Methadone
references.citation: J Pharmacol Exp Ther. 1988 Aug;246(2):441-8
references.pmid: 2457074
references.citation: Cold Spring Harb Perspect Med. 2013 Jan 01;3(1):a012104
references.pmid: 23125072
references.citation: Br J Psychiatry. 1991 Aug;159:208-12
references.pmid: 1663410
references.citation: Drug Alcohol Depend. 2009 Apr 1;101(1-2):92-100
references.pmid: 19101098
references.citation: Rev Bras Psiquiatr. 2006 Jun;28(2):153-7
references.pmid: 16810401
references.citation: J Anal Toxicol. 1999 Sep;23(5):323-32
references.pmid: 10488918
references.citation: Addict Behav. 2002 Jul-Aug;27(4):575-84
references.pmid: 12188593
references.citation: J Anal Toxicol. 1995 Oct;19(6):443-9
references.pmid: 8926739
references.citation: Psychol Sci. 2000 Nov;11(6):446-53
references.pmid: 11202488
references.citation: Neuroscience. 2013 Sep 17;248:637-54
references.pmid: 23624062
references.citation: Addiction. 2003 Mar;98(3):269-79
references.pmid: 12603227
references.citation: Am J Addict. 2009 Jul-Aug;18(4):301-8
references.pmid: 19444734
references.citation: Am J Addict. 2013 Jul-Aug;22(4):344-51
references.pmid: 23795873
references.citation: J Neurosci. 2009 Nov 25;29(47):14764-9
references.pmid: 19940171
references.citation: PLoS Med. 2008 Jul 1;5(7):e141
references.pmid: 18597549