Effects of tetrahydrocannabinol content on marijuana smoking behavior, subjective reports, and performance.
S J Heishman, M L Stitzer, J E Yingling
Pharmacology, biochemistry, and behavior September 1989 DOI: 10.1016/0091-3057(89)90369-9 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Within-subject dose-response experiment Peer reviewed |
|---|---|
| Sample size | 12 |
| Population | Male subjects with histories of moderate marijuana use |
| Dose | 0, 1.3, or 2.7% delta 9-THC |
| Measures | forward and reverse digit span task, digit symbol substitution task, divided attention task |
| Topics | Cannabis |
| Key findings | Smoking marijuana cigarettes with higher THC content produced smaller puff and inhalation volumes and shorter puff duration, while heart rate increased dose dependently and active marijuana increased subjective drug-effect reports over placebo. Memory was impaired on digit span, and the high dose impaired digit symbol substitution, but divided attention was unaffected. The authors suggest that individual variation in smoking topography means precise control of smoking would improve dose delivery accuracy. |
Abstract
This study investigated the smoking topography of marijuana and its effect on heart rate, subjective reports, and cognitive/psychomotor task performance. Male subjects (N = 12) with histories of moderate marijuana use smoked ad lib one cigarette containing 0, 1.3, or 2.7% delta 9-THC on separate days. Smoking topography measures revealed smaller puff and inhalation volumes and shorter puff duration for the high marijuana dose compared to the low dose. No other smoking behavior differed between the active doses. Heart rate was increased dose dependently over placebo levels. Active marijuana also increased subjective reports of drug effect over placebo, but not dose dependently. Significant memory impairment was observed on a forward and reverse digit span task, and performance was impaired on the digit symbol substitution task by the high, but not low, dose of marijuana. Performance on a divided attention task was not affected by marijuana. Thus, although subjects adjusted their smoking of cigarettes varying in THC content, dose-related effects of marijuana were obtained on several measures. The observed differences and individual variation in smoking topography measures suggest that precise control of smoking behavior would improve the accuracy of marijuana dose delivery.