Globally, an estimated 400 million people live with an alcohol use disorder alone, with 209 million of those meeting criteria for alcohol dependence. When drug use disorders are included, the number climbs substantially higher. In the United States, tens of millions of people meet the clinical threshold for a substance use disorder in any given year, and the ripple effects reach far beyond those individuals.
Global Numbers at a Glance
The World Health Organization reported in 2024 that substance use contributes to over 3 million deaths worldwide each year, with the majority among men. The 400 million figure for alcohol use disorders alone makes it one of the most common health conditions on the planet, comparable in scale to diabetes. That number covers a spectrum from mild patterns of problem drinking to severe dependence requiring medical support to quit safely.
Drug use disorders, including those involving opioids, stimulants, and cannabis, add tens of millions more to the global total. The combined burden places substance use disorders among the leading causes of disability worldwide, driving hospitalizations, infectious disease transmission, and preventable death across every region.
How Many Americans Are Affected
The U.S. carries a disproportionate share of the global burden. The federal government’s annual household survey consistently finds that roughly 46 to 48 million Americans aged 12 and older meet diagnostic criteria for a substance use disorder in a given year. That includes disorders involving alcohol, illicit drugs, or prescription medications used outside their intended purpose.
To put that in perspective, about 1 in 6 Americans aged 12 and older qualifies. Alcohol use disorder accounts for the largest share, but opioid, stimulant, and cannabis use disorders each affect millions on their own. About 21.2 million U.S. adults have what clinicians call a co-occurring condition: a substance use disorder alongside a separate mental health disorder such as depression, anxiety, or PTSD. This overlap is the norm rather than the exception, and it complicates both diagnosis and recovery.
The Opioid Crisis in Numbers
Opioids remain the deadliest category of substances in the United States, though recent trends show improvement. CDC data for 2024 show that heroin-involved deaths dropped to about 2,743 (a rate of 0.8 per 100,000 people), down 33% from the prior year. Deaths involving prescription opioids like oxycodone and hydrocodone fell about 21%, to roughly 7,989 deaths.
Synthetic opioids, primarily illicitly manufactured fentanyl, still drive the majority of overdose fatalities. The total number of drug overdose deaths in the U.S. peaked near 112,000 in a single year before beginning to decline. Even with that decline, overdose remains a leading cause of death for Americans under 50. The economic toll is staggering: a 2017 analysis by the CDC estimated that opioid use disorder and fatal opioid overdose together cost the U.S. economy roughly $1 trillion in a single year, factoring in healthcare, lost productivity, criminal justice costs, and reduced quality of life.
Children and Families Bear the Cost
Substance use disorders don’t stay contained to the person using. Nearly 19 million U.S. children, about 1 in 4, lived with at least one parent or primary caregiver who had a substance use disorder in 2023, according to research highlighted by the National Institutes of Health. That exposure increases a child’s risk of developmental delays, mental health conditions, academic struggles, and eventually developing a substance use disorder themselves.
Households affected by substance use also face higher rates of housing instability, domestic violence, and involvement with the child welfare system. The effects compound across generations, which is one reason public health experts frame substance use disorders as a family condition, not just an individual one.
The Gap Between Need and Treatment
One of the most persistent problems is that most people who qualify for treatment never receive it. Historically, fewer than 1 in 10 Americans with a substance use disorder access specialized treatment in any given year. Barriers include cost, lack of available programs, stigma, long wait times, and not recognizing the problem as something that warrants professional help.
The 21.2 million adults managing both a mental health condition and a substance use disorder face an especially difficult path. Treatment programs that address only one condition tend to produce worse outcomes, yet integrated programs remain unevenly available across the country. Rural areas are hit hardest, often lacking both addiction specialists and mental health providers within a reasonable distance.
Who Is Most at Risk
Substance use disorders cross every demographic line, but certain groups face higher rates. Men are roughly twice as likely as women to develop a substance use disorder and account for the majority of overdose deaths globally. Young adults aged 18 to 25 consistently show the highest rates of illicit drug use and binge drinking. Indigenous and Native American communities in the U.S. experience overdose death rates significantly above the national average.
Socioeconomic factors play a major role as well. People experiencing homelessness, those with histories of incarceration, and individuals with untreated trauma or chronic pain are all at elevated risk. That said, substance use disorders also affect people with stable jobs, homes, and families. The condition does not follow a single profile, which is part of why it remains underdiagnosed across income levels and age groups.
Why the Numbers Keep Growing
Several forces have expanded the scope of substance use disorders over the past two decades. The oversupply of prescription opioids in the early 2000s created a wave of dependence that shifted to heroin and then to fentanyl as prescribing tightened. Alcohol consumption increased during and after the COVID-19 pandemic, with studies showing lasting upticks in heavy drinking among middle-aged adults. The growing availability of high-potency cannabis products has also contributed to rising rates of cannabis use disorder, particularly among younger users.
At the same time, screening and diagnosis have improved, meaning some of the increase in reported numbers reflects better detection rather than a true spike in new cases. Still, the trajectory is clear: substance use disorders affect a larger share of the population today than they did 20 years ago, and the substances involved are more potent and more lethal than in previous generations.