Alcohol and marijuana: comparative dose effect profiles in humans.

Area of Science:

• Neuroscience
• Pharmacology
• Psychology

Background:

• Understanding the comparative effects of alcohol and marijuana is crucial for public health and safety.
• Both substances are widely used, but their distinct subjective and performance-impairing effects require detailed examination.

Purpose of the Study:

• To compare the dose-dependent subjective and performance effects of oral alcohol and smoked marijuana.
• To investigate the relationship between subjective drug experiences and objective behavioral impairment.

Main Methods:

• A double-blind, randomized crossover study involving 6 male subjects with moderate alcohol and marijuana use history.
• Administration of three doses of alcohol (0, 0.6, 1.2 g/kg) and three doses of marijuana (0, 1.3, 2.7% delta 9-THC).
• Assessment of subjective drug effects and performance on cognitive tasks, alongside physiological monitoring.

Main Results:

• Both alcohol and marijuana produced dose-dependent subjective effects.
• Higher alcohol doses led to significant performance impairments on multiple tasks (circular lights, tracking, DSST).
• Marijuana caused minimal performance impairment, primarily on DSST speed, with similar subjective effects across active doses.

Conclusions:

• Smoked marijuana's subjective and performance effects were comparable to a low dose of alcohol (0.6 g/kg).
• Alcohol demonstrated a greater capacity for performance impairment compared to marijuana at the tested doses.
• The findings aid in understanding the relative risks and effects of alcohol and marijuana consumption.