Subjective and physiological effects, and expired carbon monoxide concentrations in frequent and occasional cannabis smokers following smoked, vaporized, and oral cannabis administration

Matthew N. Newmeyer, Madeleine J. Swortwood, Osama A. Abulseoud, Marilyn A. Huestis

Research output: Contribution to journalArticlepeer-review

Abstract

Background Although smoking is the most common cannabis administration route, vaporization and consumption of cannabis edibles are common. Few studies directly compare cannabis’ subjective and physiological effects following multiple administration routes. Methods Subjective and physiological effects, and expired carbon monoxide (CO) were evaluated in frequent and occasional cannabis users following placebo (0.001% Δ9-tetrahydrocannabinol [THC]), smoked, vaporized, and oral cannabis (6.9% THC, ∼54 mg). Results Participants’ subjective ratings were significantly elevated compared to placebo after smoking and vaporization, while only occasional smokers’ ratings were significantly elevated compared to placebo after oral dosing. Frequent smokers’ maximum ratings were significantly different between inhaled and oral routes, while no differences in occasional smokers’ maximum ratings between active routes were observed. Additionally, heart rate increases above baseline 0.5 h after smoking (mean 12.2 bpm) and vaporization (10.7 bpm), and at 1.5 h (13.0 bpm) and 3 h (10.2 bpm) after oral dosing were significantly greater than changes after placebo, with no differences between frequent and occasional smokers. Finally, smoking produced significantly increased expired CO concentrations 0.25–6 h post-dose compared to vaporization. Conclusions All participants had significant elevations in subjective effects after smoking and vaporization, but only occasional smokers after oral cannabis, indicating partial tolerance to subjective effects with frequent exposure. There were no differences in occasional smokers’ maximum subjective ratings across the three active administration routes. Vaporized cannabis is an attractive alternative for medicinal administrations over smoking or oral routes; effects occur quickly and doses can be titrated with minimal CO exposure. These results have strong implications for safety and abuse liability assessments.

Original languageEnglish (US)
Pages (from-to)67-76
Number of pages10
JournalDrug and alcohol dependence
Volume175
DOIs
StatePublished - Jun 1 2017
Externally publishedYes

Keywords

  • Cannabis
  • Carbon monoxide
  • Edibles
  • Heart rate
  • Subjective effects

ASJC Scopus subject areas

  • Toxicology
  • Pharmacology
  • Psychiatry and Mental health
  • Pharmacology (medical)

Fingerprint

Dive into the research topics of 'Subjective and physiological effects, and expired carbon monoxide concentrations in frequent and occasional cannabis smokers following smoked, vaporized, and oral cannabis administration'. Together they form a unique fingerprint.

Cite this