Effects of Food Deprivation on Subjective Effects and Self-Administration of Marijuana in Humans

Abstract

The effects of fasting on the intake and subjective effects of marijuana were studied in five marijuana smokers. A within-subjects design was used in which subjects smoked either active (0.8 and 3.6% THC) or placebo (0.0% THC) marijuana after eating normally or after fasting for 24 hr. Six experimental sessions were conducted in a randomized order. Each 3-hr. session consisted of two periods: a sampling period in which subjects took 4 controlled puffs from a cigarette of a given potency, followed about one hour later by a 30-min. self-administration period, in which subjects could smoke as much or as little of the sampled marijuana as desired. Subjective and physiological measures (i.e., carbon monoxide level and heart rate) were assessed before and 5, 20, and 60 min. after the four puffs during the sampling period. During the self-administration period, the number of puffs taken was recorded. Dose-dependent effects of marijuana, such as elevated heart rate and “high” ratings, were observed during the sampling period, but these effects of marijuana were not affected by the feeding manipulation. Subjects varied widely in their marijuana self-administration, but self-administration was not systematically affected by fasting. We conclude that an acute period of food deprivation does not affect the mood-altering effects of different potencies of marijuana. We could not adequately demonstrate whether fasting increases the reinforcing efficacy of marijuana, since self-administration rate of active marijuana did not exceed that of placebo marijuana self-administration.