Substance abuse, also known as substance use disorder, is a pattern of using drugs or alcohol in a way that causes significant problems or distress to an individual. This can include failure to meet responsibilities at work, school, or home, using substances in dangerous situations (such as driving), legal issues related to substance use, and ongoing use despite social or interpersonal problems caused by the substance

. It involves the harmful or hazardous use of psychoactive substances, including alcohol, illegal drugs, and misuse of prescription medications. Substance abuse can lead to physical and psychological dependence, changes in brain structure and function, and long-term health and social consequences

. Key characteristics of substance abuse include:

• Excessive or prolonged use of substances like alcohol, tobacco, opioids, marijuana, cocaine, and others

• Continued use despite negative effects on health, relationships, and daily functioning

• Development of tolerance (needing more to achieve the same effect) and withdrawal symptoms when not using the substance

• It is considered a medical brain disorder with both genetic and environmental influences contributing to its development

In summary, substance abuse is the harmful or hazardous use of substances that leads to significant impairment in personal, social, or occupational functioning and may result in addiction or substance dependence if untreated