Related Experiment Video
Updated: Aug 7, 2026
07:30
Brain Morphology of Cannabis Users With or Without Psychosis: A Pilot MRI Study
Published on: August 18, 2020
Patterns of simultaneous polysubstance use in drug using university students
Sean P Barrett1, Christine Darredeau, Robert O Pihl
1Department of Psychology, McGill University, Montreal, Quebec, Canada.
Human Psychopharmacology
|June 20, 2006
Summary
Simultaneous polysubstance use (SPU) is common, with alcohol often initiating combined use of other drugs. Tobacco consumption also increases when used with various substances, indicating complex co-administration patterns.
Area of Science:
- Psychology
- Neuroscience
- Public Health
Background:
- Simultaneous polysubstance use (SPU) is prevalent but poorly understood.
- Limited research exists on the specific patterns of co-administered substances.
Purpose of the Study:
- To investigate the co-administration patterns of various substances among university students.
- To determine the order, type, and quantity of substances used together.
Main Methods:
- 149 drug-using university students completed structured interviews.
- Detailed information on substance type, order, and quantity during co-administration was collected.
- Statistical analyses (chi-squared tests, t-tests) were employed.
Main Results:
- Alcohol frequently initiated the use of other co-administered substances like cannabis, cocaine, and MDMA.
- Alcohol consumption increased when used with cocaine and methylphenidate.
- Tobacco use significantly increased when combined with alcohol, cannabis, and various stimulants.
Conclusions:
- SPU is a routine behavior with specific co-administration patterns.
- The sequence and context of substance use are influenced by other co-administered drugs.
Related Concept Videos
01:24Substance Use Disorders Affecting Sleep
Substance use disorders involve a pattern of using drugs more extensively than intended and continuing use despite harmful consequences. This includes legal substances like alcohol and nicotine, as well as illegal drugs. These disorders often involve both physical and psychological dependence, reflecting compulsive use of substances that significantly alter thoughts, feelings, and behaviors, contributing to a major public health issue.
Understanding the concepts of physical dependence,...
Understanding the concepts of physical dependence,...
01:15Drug Abuse and Addiction: Pharmacological Phenomena
Drug dependence, abuse, and addiction are complex phenomena that can precipitate various abnormal states. Physical dependence refers to a state of pharmacological adaptation to a drug. This adaptation often results in tolerance—a reduced response to the drug after repeated administrations. When the drug use is abruptly stopped, withdrawal symptoms occur due to the body's need to readjust from the pharmacologically induced imbalance. However, tolerance and withdrawal symptoms do not necessarily...
01:27Combined Effects of Drugs: Synergism
Synergism is a useful mechanism where combining two or more drugs is more effective than each constituent used alone. Such combinations are also called supra-additive interactions. The drugs collectively enhance the final therapeutic effect by acting on different targets. Another advantage is that the low dose of each constituent drug is sufficient to achieve the desired effect. This helps reduce the duration of therapy and lower the adverse effects of these drugs.
Such synergistic combinations...
Such synergistic combinations...
01:17Drug Dependence
Medications are typically administered to achieve therapeutic effects. Some drugs can modify an individual's mood and perception, frequently resulting in various enjoyable experiences. However, this can result in drug dependency, a condition marked by continuous drug use despite potential negative consequences. Drug dependency primarily falls into two categories: psychological and physical dependence. Psychological dependence occurs when the pleasurable feelings induced by the drug...
01:21Drug Accumulation During Multiple Dosing: Repetitive IV Injections
Calculating drug dosage and accumulation in multiple-dose regimens is crucial for achieving therapeutic efficacy while avoiding toxicity. This involves determining the plasma drug concentrations over time to optimize dosing schedules. The principle of superposition is fundamental in this process, allowing for the prediction of drug concentration in plasma following multiple doses based on single-dose data.The principle of superposition asserts that the plasma concentration-time curves from...
01:28An Overview of Psychoactive Drugs
Psychoactive drugs impact brain function, influencing perception, mood, consciousness, cognition, and behavior. These substances are grouped based on their effects and the mechanisms by which they act.
Stimulants such as cocaine, amphetamines, and nicotine enhance brain activity, leading to increased alertness, attention, and energy. These drugs typically raise heart rate, blood pressure, and body temperature. While they can induce feelings of euphoria, their misuse can result in severe health...
Stimulants such as cocaine, amphetamines, and nicotine enhance brain activity, leading to increased alertness, attention, and energy. These drugs typically raise heart rate, blood pressure, and body temperature. While they can induce feelings of euphoria, their misuse can result in severe health...