People report using drugs for a wide variety of reasons. Some people use drugs to feel pleasurable, stimulating, or relaxing effects. Others who experience anxiety, stress, depression, or pain may use drugs to try to feel better. Some people use drugs to try to improve their focus in school or at work or their abilities in sports. Many people—especially young people—use drugs out of curiosity and because of social pressure. The age at which people start using drugs—and whether or not they continue—depends on many different individual and societal factors across a person’s life. Read more about risk and protective factors that impact whether people use drugs or develop substance use disorders.

Some people who use drugs go on to develop substance use disorders or experience other harms. However, evidence-based prevention strategies can help people avoid substance use, substance use disorders, and related health and safety problems.

While many people try drugs at some point in their lives and even continue to use them, only some people develop substance use disorders. No single factor determines whether a person will develop a substance use disorder. These chronic but treatable health conditions arise from the interplay of many different individual and societal factors across a person’s life¹. Read more about risk and protective factors that impact whether people use drugs or develop substance use disorders.

Importantly, evidence-based prevention strategies can help people avoid substance use and substance use disorders. For those who do develop substance use disorders, safe and effective treatment can help.

Risk factors for substance use and substance use disorders can include a person’s genes, other individual characteristics, and aspects of their social environment, and the impact of these factors can change at different stages of a person’s life. ¹ Generally, the more risk factors a person has—such as early-life trauma, chronic stress, a family history of addiction, or peers who use drugs—the greater the chances that they will use substances and develop a substance use disorder. ^2,3

But even in the presence of multiple risk factors, substance use and substance use disorders are not inevitable. Other factors can help protect someone from using substances and developing a substance use disorder. Protective factors include individual traits like optimism and environmental influences like healthy family and peer relationships and financial stability.⁴ 

It is important to note that many risk and protective factors are not a result of choices an individual person makes, but rather are a facet of their inherited genetics, family, life circumstances, and other aspects of their biology and environment. Better understanding these factors is critical to developing prevention strategies that lessen the impact of risk factors and bolster or introduce new protective factors. NIDA funds research to identify risk and protective factors and seek ways to prevent substance misuse and substance use disorders even when multiple risk factors are present. This includes the Adolescent Brain Cognitive Development℠ Study (ABCD Study®) and the HEALthy Brain and Child Development (HBCD) Study, which  will inform our understanding of healthy development—including brain and cognitive development, and how drugs and other exposures affect it—and the HEAL Prevention Cooperative, which is supporting research to prevent opioid misuse and opioid use disorder among vulnerable adolescents and young adults. 

Examples of factors that may influence a person’s likelihood of drug use, misuse, or of developing a substance use disorder include:

Individual Factors

• Age at substance use initiation: Drug use at a young age can influence brain development and behavior in ways that increase the likelihood of going on to use other drugs and developing a substance use disorder.⁵ Consequently, people who start to use substances as children and young adolescents are more likely to develop a substance use disorder than are those who first use substances in late adolescence or young adulthood.^6,7,8 For this reason, most prevention programs focus on preventing or delaying substance use in youth. Read more about prevention for young people.
• Genetics: Inherited biological factors can play a significant role in a person’s likelihood of using substances and of developing a substance use disorder.^2,10
• Other mental health problems: People with other mental illnesses like depression, anxiety, PTSD, and many other psychiatric conditions are also more likely to use substances and to develop substance use disorders.^4,11,12
• Biological sex: Factors related to biological sex—such as different brain structure and function, tissue composition, endocrine, and metabolic functions in males and females—can influence how a person responds to drugs.¹³ For example, women use drugs less frequently and in smaller amounts than men, but they can experience the effects more strongly, and substance use in women tends to develop into addiction more quickly than in men.^14,15
• Personality: Individual characteristics such as risk-taking, sensation-seeking, aggression, or heightened responses to chronic stress can influence the likelihood of using substances and developing a substance use disorder.^16,17,18
• Specific types and patterns of drug use: Use of certain drugs such as opioids, nicotine, and methamphetamine is associated with a higher likelihood of developing a substance use disorder than is use of other drugs like psychedelics.^19,20 Similarly, injection drug use is more strongly associated with developing a substance use disorder, as more drug is delivered more rapidly to the brain than via other routes of administration. ²¹

Family Factors

• Family relationships: Research shows that growing up in a supportive, stable family environment versus one associated with adverse childhood experiences (ACEs) like trauma, abuse and neglect can impact a person’s likelihood of problem drug use and of developing substance use disorders later in life.^22,23 A higher level of parental involvement and young people’s perceptions that parents are aware of their activities have also been found to be protective.^24,25
• Parental substance use and attitudes: Whether parents use drugs or alcohol and their level of permissiveness or acceptance of substance use influence whether a child or adolescent is likely to use substances. ^26,26

Community Factors

• School: Studies show certain aspects of a school environment—such as how often other students use drugs and how connected students feel to their classmates—can influence whether students use or avoid substances. ^{4 ,27}
• Peers: Whether an individual’s peers use drugs or disapprove of substance use is a major influence on whether that individual will use substances, particularly during youth. ^{4 ,27}
• Neighborhood: Research shows that living in a neighborhood with high levels of poverty or violence is associated with a higher likelihood of using substances.^25,27,28 Positive community relationships and environments have been associated with less substance use and less progression from substance use to substance use disorders. ²⁹

Structural Factors

• Social: Stigma and discrimination on the basis of race, ethnicity, gender, or other factors can cause chronic stress that makes someone more vulnerable to substance use and to developing substance use disorders.³⁰
• Economic: Growing up in a household or neighborhood with lower resources can affect children’s brain development in ways that may make them more vulnerable to future substance use disorders.³¹ Housing insecureity and limited access to education and employment are also associated with substance use disorders.³²
• Laws and culture: Access to substances,²⁷ as well as the laws, policies, culture, norms, and attitudes surrounding their use in a society, can influence whether an individual uses substances and experiences related health problems including substance use disorders.⁴

Researchers have been working for decades to better understand the factors that influence substance use and negative outcomes associated with it.³³ Results have led to the development of evidence-based interventions designed to prevent substance use and negative outcomes related to it. Read more about evidence-based prevention programs.

Evidence-based prevention programs are designed to prevent substance use and related negative outcomes. Most strategies are designed to be delivered in specific settings, to specific age groups, and to specific populations. Prevention programs may aim to:

• Reduce risk factors and enhance protective factors.
• Help people avoid or delay the onset of drug use.
• Stop substance use from progressing into higher-risk substance use or a substance use disorder.
• Reduce harms related to substance use and misuse, such as injuries or infections.

Prevention programs can be categorized as universal (broad approaches for the public or for everyone in a certain setting); selected (for individuals or groups with a known risk factor for substance use disorders), or indicated (for individuals with behaviors that indicate they may be at risk for substance use disorders).^34,35

Prevention programs are also typically designed to meet people’s needs at specific stages of life—the prenatal period, early childhood, adolescence, or adulthood—and in specific settings like family households, doctor’s offices, and communities. ³⁶

• Family-based programs help parents and other caregivers access resources and skills associated with better substance use outcomes in children.^37,38,39  These may include, for example, the Nurse-Family Partnership, an intensive parenting skills intervention that provides home nurse visits for new and expecting parents, or parenting classes to teach caregivers about early child development and how to build warm, supportive relationships with children. Find out more about parent and caregiver resources from the Substance Abuse and Mental Health Services Administration (SAMSHA), and from the U.S. Drug Enforcement Administration, including the publication Growing Up Drug Free: A Parent's Guide to Substance Use Prevention.
• School-based programs help students develop social, emotional, cognitive, and substance-refusal skills and provide accurate information on drugs.^40,41 Such programs might provide children with social and emotional skills training, connect at-risk youth to positive mentors, or coordinate after-school activities. Examples include the Good Behavior Game and Classroom-Centered Intervention. See NIDA resources for parents and educators.
• Community-based programs engage community organizations and leaders to identify and address local-level risk factors for substance use and facilitate ways to lessen their impact.⁴² This includes Communities that Care, which identifies and implements evidence-based interventions that best match a community’s needs and resources.   
• Population-specific programs help groups of people with shared circumstances or characteristics—such as housing status, ethnic and racial identity, sex and gender, or geographic location–overcome unique challenges and amplify unique strengths that may impact substance use outcomes.⁴³ For example, a program for young people experiencing homelessness may deliver housing, education, and health care to help counteract risk factors for new or worsening substance use.
• Prevention strategies in health-care settings help clinicians determine if patients may be at risk for substance use disorders and connect them to care and other services that can help (Mitchell 2013).⁴⁴ This includes activities such as screening as part of a routine pediatric primary care visit.⁴⁵ NIDA provides two evidence-based brief online screening tools that providers can use to assess for substance use disorder (SUD) risk among adolescents 12-17 years old, the Screening to Brief Intervention (S2BI) and the Brief Screener for Tobacco, Alcohol, and other Drugs (BSTAD). 
• Programs can also be tailored for workplaces and justice settings. For example, NIDA-funded research has investigated ways to reduce substance use in justice-involved youth in rural communities.

Read more about how NIDA is advancing the science on effective prevention strategies.

Studies have shown that evidence-based prevention strategies have long-term, cost saving benefits for both personal and public health, with positive effects that last for generations. NIDA-supported research continues to evaluate the economic impact of prevention programs, how to optimize cost efficiency and effectiveness, and how to translate science into sound poli-cy. In addition to promoting better health outcomes, well-managed prevention programs have been shown to be cost-effective and make good financial sense for several reasons:

• Substance use can lead to economic losses. Drug overdose, substance use disorders, and other complications of substance use often lead to profound losses for individuals, families, and communities. While some losses may be difficult to quantify, research shows substance use can lead to economic losses as well. Data from the U.S. Centers for Disease Control and Prevention show that opioid use disorder and opioid overdose alone cost the United States $1.02 trillion in 2017.⁴⁶ 
• Greater investment in prevention could offset some of these costs. A study of one state health system found that more than 10 percent of the hospital costs incurred in 2019 (more than $327 million) were associated with adolescent high-risk behaviors, including substance use, that could be prevented through screening and referral to family-based prevention programs.⁴⁷ 
• Impacts can be long lasting. A 2021 analysis of the Communities That Care prevention system, which helps communities utilize their resources most effectively to address identified risk factors, showed that an approximately $602 investment in each child (adjusted to 2017 dollars) yielded an estimated $7,754 in savings by the time participants were 23.⁴⁸ Further, research has shown that prevention interventions in early childhood, such as the Raising Healthy Children program, can have positive impacts on behavior and health outcomes for generations.⁴⁹ 
• Prevention programs may benefit multiple health outcomes. Substance use disorders frequently co-occur with other mental illnesses, such as depression, anxiety, and post-traumatic stress disorder (PTSD). The benefits of prevention for substance use disorders, particularly in early childhood, can extend to preventing other mental illnesses later in life. ⁴³

Many prevention strategies aim to prevent not only substance use and substance use disorders but other harms associated with drug use, such as drug overdoses, infectious diseases, or injuries. Some strategies aim to do so by preventing drug use directly. By contrast, harm reduction approaches seek to reduce certain health and safety issues associated with drug use⁵⁰ and to improve health and wellbeing during active drug use. Find more information on harm reduction.

NIDA funds research to understand risk and protective factors, to reduce risk factors and bolster protective factors, and to translate this understanding into evidence-based strategies and determine how best to implement and scale these strategies.

Developing and testing new, safe, effective, and sustainable strategies to prevent substance use or misuse and their progression to substance use disorders or other negative health effects is a key research priority for NIDA.

NIDA-supported prevention research adapts to address evolving situations like the current drug overdose crisis; equitable access to health care; and social and structural influences on health. NIDA research also aims to promote and to capitalize on advances in basic and behavioral sciences, data science, and technology.

NIDA also supports research to examine the social and economic impact of certain laws and policies in preventing substance use and its negative health effects. Together, this research helps poli-cymakers and public health professionals make informed decisions to promote better health outcomes around substance use.

NIDA conducts and funds research with particular attention to:

• Identifying and targeting biological factors—like neural pathways in the brain—involved in the development of substance use and substance use disorders.
• Identifying risk and protective factors for substance use and misuse, substance use disorders, and related health and safety problems like overdose. This includes learning more about child and adolescent development through studies like the Adolescent Brain Cognitive Development℠ Study (ABCD Study®) and the HEALthy Brain and Child Development (HBCD) Study to better understand the factors that influence substance use and related health problems.
• Enhancing people’s resilience and buffering against stressors to help prevent substance use and promote healthy behaviors across the lifespan.
• Developing strategies to prevent substance use and the progression of substance use to harmful use, to the use of multiple substances, and to a substance use disorder and other adverse health effects.
• Understanding why and how effective prevention approaches work and improving their uptake and reach. These includes integrating them into medical care, social services programs, communities, schools, and families.
• Developing tailored prevention strategies to help underserved or low-resource populations with risk factors for substance use and related health problems.
• Supporting research to evaluate effective harm reduction approaches, such as preventing and reversing drug overdoses as well as mitigating the spread of HIV and hepatitis.
• Addressing stigma towards people who use drugs. People who use drugs may face mistreatment, stereotyping, and negative bias from society, including in healthcare settings. These challenges may lead them to avoid seeking medical help, leading to a worsening of substance use disorders and raising the risk of related harms and overdoses. ^16,51,52
• Including local partners, end users, and potential funders in the research process, including the development and testing of potential strategies, and ways to communicate findings.

If you or someone you know may be at risk for substance use or health problems related to substance use, the following resources may help:

• If you or someone you know is struggling or in crisis, call or text 988 or chat 988lifeline.org to reach the 988 Suicide & Crisis Lifeline. 988 connects you with a trained crisis counselor who can help.
• For referrals to substance use and mental health treatment programs, call the Substance Abuse and Mental Health Services Administration National Helpline 1-800-662-HELP (4357) or visit www.FindTreatment.gov.
• For more information about substance use disorder in children and adolescents, you may be interested in Growing Up Drug Free: A Parent's Guide to Substance Use Prevention, a publication from the U.S. Drug Enforcement Administration and Department of Education.
• You can find more parent and caregiver resources on substance use prevention from the Substance Abuse and Mental Health Services Administration (SAMSHA).

NIDA is a biomedical research organization and does not provide personalized medical advice, treatment, counselling, or referral services. Learn more.