The terms “drunk” and “high” describe two distinct states of altered consciousness resulting from the use of alcohol and cannabis, respectively. While both substances are psychoactive and temporarily change the user’s experience, they operate on the body and brain through entirely different biological pathways. Understanding the fundamental differences between alcohol intoxication and cannabis intoxication is important for assessing personal safety, predicting behavioral outcomes, and informing public health and legal policies. The resulting physical and mental effects are unique to each substance, leading to varied levels of impairment.
Distinct Mechanisms of Action
Alcohol functions broadly as a central nervous system (CNS) depressant, affecting nearly all tissues and neural communication pathways throughout the body. Its primary action involves enhancing the effects of gamma-aminobutyric acid (GABA), the brain’s main inhibitory neurotransmitter. By boosting GABA activity at the GABAA receptor, alcohol essentially slows down brain function, leading to the characteristic sedative and anxiety-reducing effects. Alcohol also inhibits glutamate, the brain’s primary excitatory neurotransmitter, particularly at the N-methyl-D-aspartate (NMDA) receptors. This dual action—increasing inhibition and decreasing excitation—contributes to the global reduction in neural activity and the cognitive impairments seen during intoxication.
The psychoactive component of cannabis, delta-9-tetrahydrocannabinol (THC), interacts with the body’s natural Endocannabinoid System (ECS). THC binds primarily to the cannabinoid receptor type 1 (CB1) receptors, which are highly concentrated in areas of the brain that govern memory, coordination, and pleasure. This interaction acts as a neuromodulator, typically reducing the release of other neurotransmitters. The effects of THC are more localized and specific to the ECS pathways rather than the systemic depression caused by alcohol.
Observable Physical Differences
Alcohol intoxication results in pronounced physical signs tied to central nervous system depression and systemic toxicity. Motor coordination is severely impaired, often resulting in an unsteady gait, slurred speech due to reduced muscle control, and significantly decreased reflexes. Physiological signs can include flushed skin and a sensation of warmth from peripheral vasodilation, as well as nausea and vomiting as the body attempts to expel the toxin.
The physical manifestations of being high on cannabis are generally less disruptive to gross motor function, though reaction time and fine motor skills are still affected. Hallmark physical signs of THC exposure include bloodshot eyes, which result from vasodilation, and xerostomia, commonly known as “dry mouth.” THC also frequently causes an increase in heart rate, known as tachycardia, and a notable increase in appetite, often referred to as “the munchies,” due to its action on CB1 receptors in the hypothalamus.
Cognitive and Perceptual Changes
The cognitive effects of being drunk are characterized by a breakdown of executive functions, leading to impaired judgment and reduced inhibitions. Alcohol impairs the ability to process information quickly and logically, resulting in slowed cognitive speed and an increased likelihood of emotional volatility. Higher doses can lead to memory blackouts, where no recollection of events is formed due to alcohol’s severe disruption of memory formation in the hippocampus.
Cannabis intoxication most often introduces alterations in sensory and time perception. Users frequently report a distortion of time, where moments seem to stretch or pass slowly, and an enhancement of sensory input, making colors seem brighter or sounds more intense. THC significantly impairs short-term memory and concentration, often leading to a fragmented thought process. While the experience can be euphoric or introspective, higher doses may trigger acute anxiety, paranoia, or feelings of social withdrawal in some individuals.
Comparative Safety Profiles and Duration
Alcohol is characterized by a rapid onset of effects, particularly when consumed on an empty stomach, and a relatively short half-life, meaning the body metabolizes it at a steady, measurable rate. The acute safety profile of alcohol is poor, as its effects are strongly dose-dependent, and consumption carries a clear risk of lethal overdose due to respiratory depression. The brainstem, which controls breathing and heart rate, is highly sensitive to the systemic depressant action of alcohol.
Cannabis has a very low risk of fatal overdose because CB1 receptors are sparsely located in the brainstem, preventing THC from directly shutting down autonomic functions like respiration. The duration of cannabis effects varies widely depending on the method of consumption; inhaled cannabis produces a rapid onset and a shorter duration of effects (typically 1 to 4 hours), while edibles have a delayed onset (30 minutes to 2 hours) and a significantly longer duration (4 to 8 hours or more). The public health risks and acute toxicity associated with cannabis are substantially lower than those associated with alcohol.