Drug and Substance Abuse

Medically reviewed by Leigh Ann Anderson, PharmD. Last updated on June 29, 2025.

Drug abuse: a national epidemic

The abuse of drugs or other substances, whether they are illegal drugs or prescription opioid drugs, alcohol or tobacco is one of the nation's most pressing public health issues. According to a survey published by the Substance Abuse and Mental Health Services Administration (SAMHSA) in 2023, about 47 million people aged 12 or older (16.8%) used illicit drugs in the past month prior to the survey.

In 2023, 828,000 people aged 12 or older (or 0.3%) misused prescription fentanyl or used illegally made fentanyl (IMF) in the past year. This includes 627,000 people (or 0.2%) who used IMF in the past year. However, these estimated numbers may be low. Illegally-made fentanyl may be present in street drugs or heroin without people’s knowledge and therefore not reported.

Among people aged 12 or older in 2023, 3.1% (or 8.9 million people) misused opioids (heroin or prescription pain relievers like oxycodone or hydrocodone) in the past year, much higher than the  660,000 people who used heroin and the 336,000 people who both misused prescription pain relievers and abused heroin in the past year.

In 2023, substance use disorder (SUD) were highest among young adults aged 18 to 25 (27% or 9.2 million people), followed by adults aged 26 or older (17% or 37 million people), then by adolescents aged 12 to 17 (8.5% or 2.2 million people).

For other substances among people aged 12 or older in 2023, 59% (or about 167 million people) used tobacco products, vaped nicotine, used alcohol, or used an illicit drug in the past month (also defined as “current use”), including 47.5% (or 135 million people) who drank alcohol, 17.6% (or 50 million people) who used a tobacco product, and 9.4% (or 27 million people) who vaped nicotine. 

What is drug abuse?

Drug abuse occurs when people willingly consume illegal substances or legal, prescription drugs for the purpose of altering their mood, or getting “high”. Regular drug abuse may lead to drug addiction or other bodily harm. Drug abuse usually involves selling, buying or abusing these substances, which can lead to arrest, criminal charges, and imprisonment.

The term “drug abuse” is often associated with illegal drugs such as cocaine, heroin, or LSD. In addition, more dangerous designer drugs such as bath salts (cathinones) or club drugs such as ecstasy (MDMA) are increasingly popular. And even legal substances such as tobacco and alcohol are linked with dangerous abuse. Marijuana, while still illegal according to federal law, is now legal for recreational and / or medical use in multiple U.S. states.

Designer drugs are synthetic chemicals altered in often unknown ways to produce substances that may be more potent, and frequently more dangerous. Designer drugs may resemble the effects of other illegal drugs, because the chemical formula of a designer drug is manipulated, they often cannot be classified as illegal until state or federal regulations are changed.

Club drugs might be used by youth in all-night “rave” or dance parties, at bars and at concerts for their psychoactive effects.

Prescription opioids are often abused and stolen or created synthetically and sold on the streets as the "real" thing. These products have often been found to be contaminated with other dangerous products such as fentanyl. Fentanyl, carfentanil and nitazenes (ISO) may be found in street drugs, often unknown to the user, and may lead to overdose and death.

Another synthetic opioid group called the nitazenes (specifically, isotonitazene or "ISO") was seen in some areas in 2019. It is reportedly as deadly as fentanyl, but not as widely known. Nitazenes are not approved prescription products and appear to be smuggled into the U.S. from China. Like fentanyl, it is being mixed into other drugs that are sold on the streets and can lead to overdose and death.

ISO is often mixed with street heroin, or pressed into counterfeit pills sold on the streets that may resemble prescription drugs, like counterfeit Dilaudid 'M-8' tablets and oxycodone 'M30' tablets. In powder form, ISO appears yellow, brown, or off-white in color.

Abused substances are not always illegal

Drug abuse can also occur with legal prescription drugs used in illegal ways. For example, the level of prescription opioid (narcotics) abuse in the U.S. surpasses the abuse of many illegal drugs. The unlawful use of steroids as performance enhancing drugs like anabolic steroids seen in college-level, Olympic and professional sports has resulted in a unique set of international anti-doping standards.

Alcohol and cigarette tobacco (nicotine) use, remain as some of the top abused substances in the U.S. In 2023:

• 7.4% of adolescents aged 12 to 17 (or 1.9 million people) used tobacco products or vaped nicotine in the past month. 
• 75% of adolescents aged 12 to 17 who used nicotine products in the past month only vaped nicotine products and did not use other tobacco products.
• There were 134.7 million current alcohol users aged 12 or older, with 61.4 million people (or 45.6%) past month binge drinkers. Binge drinking was highest among young adults aged 18 to 25 (28.7% or 9.8 million people).

Ultimately, abuse of these substances can lead to serious outcomes, including:

• Alcoholism
• Chronic liver disease like cirrhosis
• Liver cancer
• Chronic Obstructive Pulmonary Disease
• Lung cancer
• Other cancer types 
• Heart disease
• Stroke
• Overdose
• Vehicle accidents or other accidents, trauma
• Death

Veterinary medicines

Increasingly, veterinary medicines are being abused or included in street drugs For example, there are reports of contamination of illegal drugs with xylazine (known as "tranq"), an FDA-approved, non-opioid animal tranquilizer and pain reliever. It may be diverted from the legal animal supply or illicitly produced. The are no approved uses of xylazine for humans.

Xylazine is not an opioid, but is sometimes added to drugs of abuse, like the opioids fentanyl or heroin, to prolong the euphoric effect, but users may not be aware they are being exposed. Overdose deaths due to xylazine have increased in recent years, and treatment with naloxone may not reverse its lethal effects.

Overview of drugs of abuse

The following documents detail common drugs or other substances of abuse, but do NOT include all possible abused prescription drugs, illicit drugs or their chemical counterparts. 

This is not all the information you need to know about illicit drugs and substance abuse and does not take the place of your healthcare provider's directions. Discuss this information and any questions you have with your doctor or other health care provider. 

• Bath Salts
• Cannabis
• Cocaine
• Devil's Breath
• Ecstasy
• GHB
• Gray Death
• Hashish (Hash)
• Heroin
• Ketamine
• Krokodil
• LSD
• Marijuana
• MDMA (Ecstasy, Molly)
• Mescaline (Peyote)
• Opium
• PCP (Phencyclidine)
• Psilocybin (Magic Mushrooms)
• Quaaludes
• Rohypnol
• Speed (methamphetamine)
• Synthetic Cannabinoids (Synthetic Marijuana, Spice, K2)
• TCP (Tenocyclidine)
• Tianeptine
• U-47700 (Pink)
• Xylazine (Tranq Dope)

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer

See also: