Concerns may include: wondering if you use or consume a substance more than a reasonable amount, noticing affects of using a substance, substance use interfering with your academics or social connections, worried about a friend or family member who is abusing substances.
Substance use in college varies among students, there is a growing number of students (one-third) that abstain from all forms of alcohol and drug use and there are some that are infrequent users and then the smaller number (~10%) of students may be developing or have an addiction to alcohol and/or drugs. Although, most students believe that "all" or "most" students drink and/or use drugs, this is simply not the case.
Each person’s motivation for substance use will be unique, but there are common reasons people turn to drugs and alcohol. College students may drink or take drugs for several reasons, including:
To feel good — Because drugs and alcohol can produce a feeling of euphoria, often called a “high,” people will abuse substances to experience this pleasurable sensation. Depending on the substance consumed, other effects may accompany or follow this intensely pleasurable period. For example, stimulants may invoke feelings of confidence and wakefulness, while opioids will induce feelings of relaxation.
To feel better — Consciously or not, some people may turn to drugs and alcohol as a way to manage stress, anxiety, and depression. This “self-medication” may relieve immediate symptoms but is likely to compound the issues in the future.
To do better — When people feel unable to perform mentally, socially, or athletically, they might choose to use substances, such as performance-enhancing drugs or stimulants.
Curiosity and desire to fit in — Experimentation, peer pressure, and a yearning to impress others lead many towards substance use. This motivation is particularly relevant to teens and young adults entering a new and potentially intimidating environment (Source: https://rehabs.com/addiction/drug-use-college-students/ ).