Acute and residual effects of marijuana: Profiles of plasma THC levels, physiological, subjective, and performance measures

Stephen J. Heishman, Marilyn A. Huestis, Jack E. Henningfield, Edward J. Cone

Research output: Contribution to journalArticle


Three experienced marijuana smokers participated in four 2-day experimental sessions in which they smoked either 0, 1, or 2 marijuana cigarettes containing 2.57% Δ9-tetrahydrocannabinol (THC) at two different times on the first day. A battery of physiological, subjective, and performance measures was repeated throughout day 1 to assess acute effects and on day 2 to measure any residual effects of marijuana. Blood samples were also repeatedly collected to examine the relationship between plasma levels and pharmacological effects of THC. Acutely, marijuana increased heart rate and subjective ratings of drug effects and slightly impaired performance on a circular lights task in all subjects. Performance was also impaired (decreased accuracy and increased response time) on serial addition/subtraction and digit recall tasks on day 1 in two subjects. On day 2, tachycardia and subjective effects of marijuana were not observed. Performance remained impaired on the arithmetic and recall tasks on day 2, although the decrements were not as large as those observed on day 1. In general, plasma THC levels covaried with the other measures. These preliminary results suggest that marijuana can adversely affect complex human performance up to 24 hours after smoking.

Original languageEnglish (US)
Pages (from-to)561-565
Number of pages5
JournalPharmacology, Biochemistry and Behavior
Issue number3
StatePublished - Nov 1990



  • Cognitive tasks
  • Marijuana
  • Physiological effects
  • Plasma THC levels
  • Psychomotor tasks
  • Residual effects
  • Subjective effects Human performance

ASJC Scopus subject areas

  • Biochemistry
  • Toxicology
  • Pharmacology
  • Clinical Biochemistry
  • Biological Psychiatry
  • Behavioral Neuroscience

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