Substance Use

Use simply means taking a substance, like having a drink, a vape or trying a drug. Many people use without developing a disorder, but no use is completely risk-free.

Even occasional use can bring risks like:

• Poorer judgment and a higher chance of accidents
• Mixing substances without meaning to, such as a fake pill containing fentanyl
• For inhalants, sudden death can happen even the first time

Misuse means using in a way that raises the chance of harm. NIDA uses the word "misuse" for prescription drugs taken in a way other than prescribed.

Examples of misuse

• Binge drinking: about 5 or more drinks for men, or 4 or more for women, in about two hours
• Taking a prescription drug that was prescribed for someone else
• Taking more of a prescription drug than prescribed, or using it to get high
• Mixing alcohol with other drugs, which makes the effects stronger

A substance use disorder (SUD) is a health condition. It involves changes in the brain’s reward, stress and self-control systems, which make it hard to stop even when using causes harm.

It can be mild, moderate or severe:

• Mild: 2 to 3 signs in the past year
• Moderate: 4 to 5 signs
• Severe: 6 or more signs

It is common. In 2024, 48.4 million people in the U.S. aged 12 or older had a substance use disorder.

The basal ganglia are a group of brain areas that drive motivation and help form habits. Scientists sometimes call part of this the brain’s "reward circuit".

Substances over-activate this circuit, which causes the "high". With repeated use, the circuit adjusts. It becomes less sensitive, so everyday rewards feel weaker and the pull of the substance gets stronger.

This area plays a part in stress and feelings like unease, irritability and anxiety. These are common feelings during withdrawal, when a substance wears off.

This circuit becomes more sensitive the more a person uses. Over time, people may use mainly to escape these bad feelings, not to feel good. This is one big reason stopping is so hard.

The prefrontal cortex powers thinking, planning, solving problems, making decisions and controlling impulses.

It is the last part of the brain to finish growing. That is one reason teens are more at risk. Brain development continues until about age 25.

With repeated use, the balance between this "brakes" area and the reward and stress areas shifts. Self-control gets weaker and seeking the substance becomes more automatic.

Alcohol is found in beer, wine, hard seltzer and liquor. In the U.S. in 2024, about 134.3 million people aged 12 or older drank alcohol in the past month.

Short-term effects

• Changes in mood, thinking, behavior and coordination
• Slower reactions and poorer judgment
• Higher risk of crashes, falls and other injuries
• Too much at once can cause alcohol overdose (also called alcohol poisoning)

Long-term risks

• Liver disease, from fatty liver to cirrhosis (scarring)
• A weaker heart muscle and higher stroke risk
• Several types of cancer, including mouth and throat, liver, breast and colon
• A weaker immune system, so you get sick more easily
• Alcohol use disorder

The World Health Organization says no level of drinking is completely risk-free. Even low amounts carry some risk.

Signs someone may be struggling

• Drinking more, or for longer, than they meant to
• Trying to cut down but not being able to
• Needing more to feel the effect
• Feeling shaky, sweaty, sick or unable to sleep as alcohol wears off
• Keeping on drinking even when it causes trouble with family, friends, school or work

Nicotine is the addictive chemical in tobacco. It is found in cigarettes, cigars, hookah, chewing tobacco, nicotine pouches, and most e-cigarettes ("vapes").

Short-term effects

• A quick "buzz" as adrenaline rises
• Faster heartbeat, breathing and higher blood pressure
• A short feeling of pleasure or calm, then cravings for more

What vape aerosol can contain

• Nicotine
• Chemicals that can cause cancer
• Heavy metals like nickel, tin and lead
• Tiny particles that reach deep into the lungs
• Flavorings such as diacetyl, which is linked to a serious lung disease

Risks and long-term effects

• Nicotine can harm the parts of a young brain that control attention, learning, mood and impulse control
• Young people can become addicted quickly
• Using nicotine as a teen may raise the risk of addiction to other drugs
• Smoking is linked to lung problems, mouth and gum problems, and certain cancers
• Vape liquid can poison small children, and batteries can catch fire or explode

Signs of nicotine addiction

• Strong cravings
• Trying to stop but not being able to
• Needing more to get the same feeling
• Feeling irritable, struggling to sleep or focus when not using

Cannabis comes from the dried leaves, flowers, stems and seeds of the cannabis plant. The main chemical that causes the "high" is THC. People smoke it, vape it, or eat it in "edibles".

Common names

• Weed, pot, grass, herb, Mary Jane, ganja
• Lab-made versions are sometimes called "Spice" or "K2"

Short-term effects

• Changes in sense of time
• Trouble thinking, remembering and moving smoothly
• Relaxation, or the opposite: anxiety, fear, panic or hallucinations, especially with strong products
• Faster heartbeat and bigger appetite

Risks and long-term effects

• Frequent or heavy use is linked to problems with learning and memory
• Studies estimate 22% to 30% of people who use cannabis have cannabis use disorder
• In people with a family risk, it is linked to earlier psychosis (losing touch with reality)
• Long-term heavy use can cause repeated severe vomiting (cannabinoid hyperemesis syndrome)
• Lung and breathing problems when smoked

Strength has gone up a lot. THC in seized cannabis rose from about 4% in 1995 to about 16% in 2022, and some products are much higher. Stronger products are linked to a higher chance of developing a disorder.

Signs someone may be struggling

• Using more often to get the same effect
• Feeling irritable, anxious, restless or unable to sleep without it
• Grades, work or hobbies slipping
• Using even when it causes problems

Opioids are a group of drugs that include heroin, illegally made fentanyl, and prescription pain relievers. They can relieve pain and cause a "high", but they also slow down breathing, which is why they can be deadly.

Common names

• Heroin: smack, black tar, chiva
• Fentanyl: has many street names, but often people do not know it is there at all

Short-term effects

• Pain relief and a rush of pleasure
• Feeling sleepy or confused
• Slowed or shallow breathing

Risks and long-term effects

• Overdose and death, because breathing can slow down or stop
• Becoming more sensitive to pain after long-term use
• Opioid use disorder
• Mixing with alcohol or other "downers" makes overdose much more likely

Illegal fentanyl is made in labs. The CDC says it is up to 50 times stronger than heroin. NIDA says as little as 2 mg, about the size of a few grains of salt, can be deadly.

Fentanyl is often mixed into heroin, cocaine and meth, or pressed into fake pills made to look like real prescription pills. You cannot see, smell or taste it. Many people who take these pills don’t know fentanyl is in them.

Signs someone may be struggling

• Often very sleepy or confused
• Tiny "pinpoint" pupils
• Needing more to feel the same effect
• Trying to cut down but not being able to
• Taking pills that were not prescribed to them

Stimulants speed up the brain and body. Cocaine is made from the leaves of the coca plant. Methamphetamine ("meth") is made in labs and is very addictive.

Common names

• Cocaine: coke, snow, crack (a smokable form)
• Meth: crystal, ice, crank, Tina

Short-term effects

• A rush of energy, confidence and alertness
• Talking a lot, eating less
• Fast heartbeat, high blood pressure, higher body temperature
• Restlessness, anxiety, panic or paranoia (feeling others are out to get you)

Risks and long-term effects

• Heart problems, heart attack, stroke and seizures
• Trouble with memory, attention and decisions
• Psychosis: seeing or hearing things, or believing untrue things
• Meth can cause serious tooth decay ("meth mouth") and sleep problems
• Snorting harms the nose, smoking harms the lungs, and sharing needles spreads HIV and hepatitis

Cocaine and meth are often mixed with fentanyl. Because cocaine wears off quickly, a person may not feel how much opioid they took. Cocaine plus alcohol makes a new chemical in the body that may be extra hard on the heart.

Signs someone may be struggling

• Unusual energy, talking a lot, or barely eating
• Trouble sleeping
• Anxiety, panic or paranoia
• Needing more to feel the same effect

Misuse means:

• Taking a prescription drug in a different way or amount than prescribed
• Taking a drug prescribed for someone else, even for a real problem like pain
• Taking a prescription drug to get high

The three groups most often misused

• Prescription pain relievers (opioids)
• Sedatives and tranquilizers ("downers")
• Prescription stimulants ("uppers")

Why it is risky

• It can lead to addiction and overdose, just like illegal drugs
• Mixing "downers" with alcohol or opioids makes the effects much stronger and more dangerous
• High amounts of stimulants can cause a dangerously high body temperature, an irregular heartbeat or seizures
• Pills sold outside a pharmacy may be fakes containing fentanyl

Signs someone may be struggling

• Taking more than prescribed, or in a different way
• Taking pills prescribed to someone else
• Seeming very sleepy and slow, or very wired
• Using prescription drugs to get high

Inhalants are chemical fumes that people breathe in to get high. Many come from cheap products found at home, school or work, like spray paint, glue, markers, correction fluid and cleaning fluids.

Common names

• Huffing, whippets, poppers, rush

Short-term effects

• Dizziness and light-headedness
• Slurred speech, slow reflexes, poor judgment
• Feeling sick and throwing up
• Confusion

Risks and long-term effects

• "Sudden sniffing death": the heart beats wrongly or breathing stops, and it can happen the very first time
• Damage to the brain and nerves, affecting memory, attention and judgment
• Damage to the heart, lungs, liver and kidneys

Signs someone may be using

• Chemical smell on breath or clothes
• Paint or stains on face, hands or clothes
• Hidden empty spray cans or chemical-soaked rags
• Seeming dazed, slurring words, or feeling sick

Hallucinogens change mood, thoughts and the way a person senses the world. Some, called psychedelics, can cause strong visions. Others, called dissociative drugs, can make a person feel detached from their body and surroundings.

Common examples and names

• LSD: acid, blotter
• Psilocybin: magic mushrooms, shrooms
• PCP (a dissociative drug)
• MDMA: ecstasy, Molly (has both stimulant and psychedelic effects)

Short-term effects

• Seeing, hearing or feeling things that are not there
• Very strong emotions, from joy to fear and confusion
• Headache, nausea, a fast heartbeat

Risks

• "Bad trips": intense fear, panic or confusion
• Accidents and injuries because judgment is affected
• Flashbacks, and rarely a lasting condition where visual changes keep coming back
• PCP can cause psychosis that lasts days to weeks
• Picking wild mushrooms can mean eating a poisonous one by mistake
• MDMA raises body temperature and heart rate; long-term use is linked to memory problems

Signs someone may be struggling

• Strange or risky behavior
• Seeming very frightened or confused
• Talking about seeing or hearing things others do not

Many substances cause a big surge of dopamine in the brain’s reward system. That can bring an intense "high" that feels much stronger than everyday fun.

The catch: with repeated use, the brain adjusts. Everyday joys can start to feel flat, and a person may need more of the substance to get the same feeling (tolerance).

Some people who live with stress, social anxiety or depression start using to feel less anxious or low. It can seem to help at first.

Depression, PTSD and ADHD often happen alongside alcohol use disorder, and a history of trauma in childhood makes people more vulnerable.

Over time, substances can make these feelings worse. As the brain’s stress system becomes more sensitive, a person may end up using just to escape the bad feelings of withdrawal.

Some people feel pressure to improve their focus at school or work, or their performance in sports. They may try stimulants or other substances hoping to get an edge.

The risks

• Taking a stimulant prescribed for someone else is misuse
• High amounts of stimulants can cause a dangerously high body temperature, an irregular heartbeat or seizures
• Pills bought outside a pharmacy may be fakes that contain fentanyl

Curiosity and wanting to fit in are very normal, especially for teens. Peer pressure can be very strong at this age.

Teens are also more at risk because the part of the brain that handles decisions and self-control is still growing. Using during these years may cause lasting brain changes.

It can feel like "everyone is doing it", but most teens are not. In 2025, 82% of 10th graders had not used marijuana, alcohol or nicotine in the past 30 days.

Easy ways to say no

• "No thanks, I’m good."
• "I’ve got practice tomorrow."
• "Not my thing."
• Suggest something else to do, or text a friend to pick you up

Your brain links use with everything around it: the friends you used with, the bar on your way home, a pipe, a bottle opener, even a time of day. Seeing these cues can flip on cravings automatically.

What helps

• Clear your home of substances and anything linked to use
• Take a different route past old spots for a while
• Spend time with people who support your goals
• Have an exit line ready: “I’ve got an early start, I’m heading off.”

Stress is one of the most common relapse triggers. Heavy use also makes the brain’s stress circuit more sensitive over time, so ordinary stress can feel bigger and the pull to use for quick relief gets stronger.

What helps

• Have a few go-to calming tools: slow breathing, a walk, a shower, music
• Break big problems into one small next step
• Talk it out with a friend, sponsor or counselor
• Protect sleep and meals in stressful weeks

Over time, many people use not to get high but to get temporary relief from discomfort. That means painful or empty feelings can become powerful triggers.

What helps

• Name the feeling: “I’m lonely, not thirsty.”
• Ride the urge: cravings rise, peak and fall like a wave, and they do pass
• Do something with your hands or body until it passes
• If feelings like low mood or anxiety keep driving use, talk to a therapist about both together

Events where others are drinking or using, or where people expect you to join in, can be some of the hardest moments. Good news, a payday or “just one to celebrate” can be as risky as a bad day.

What helps

• Bring your own non-alcoholic drink, so your hands are full
• Go with a sober buddy, and arrive and leave early
• Practise a simple “No thanks, I’m good” without explaining
• Plan a reward that isn’t a substance

Being hungry, exhausted, unwell or in physical pain lowers your ability to cope with cravings. Withdrawal can also bring anxiety, irritability and unease that push people back toward the substance.

What helps

• Eat regular meals and keep snacks handy
• Keep a steady sleep routine
• Tell your clinical provider about pain or withdrawal symptoms, so you get safe care
• Do a quick HALT check: hungry, angry, lonely, tired?

Contact with the substance itself is one of the strongest triggers. Having cash, a full fridge of drinks, or a dealer’s number in your phone makes it easy to act on an urge before you have time to think.

What helps

• Delete contacts linked to buying
• Set up automatic bill payments or savings on payday
• Carry only the cash you need
• Ask someone you trust to help you manage money for a while, if that feels right

Alcohol, cannabis and cocaine can affect judgment and raise the risk of accidents, even before any addiction. One use of an inhalant can stop the heart, and one fake pill can contain deadly fentanyl.

Taking someone else’s pills, or taking more than prescribed, can lead to addiction or overdose, just like illegal drugs.

Vapes usually contain nicotine, which is highly addictive and can harm the developing brain. The aerosol can also hold heavy metals and chemicals that can cause cancer or lung damage.

Even low amounts carry some risk. Alcohol affects judgment, increases accidents, and is linked to cancer. For some people, like those in recovery or those with certain health conditions, the safest choice is not to drink at all.

Coffee, cold showers and walking do not reverse the effects of alcohol and could make things worse. The amount of alcohol in the blood can keep rising even after someone stops drinking or passes out.

In a 2025 national survey, 91% of 8th graders, 82% of 10th graders and 66% of 12th graders said they had not used marijuana, alcohol or nicotine in the past 30 days.

Occasional use still carries risks of accidents, health problems and, over time, addiction. A single binge can cause alcohol poisoning. About one-third of U.S. alcohol deaths come from binge drinking or drinking too much at one time.

In 2024, about 3 in 4 U.S. adults who felt they had ever had a drug or alcohol problem said they were in recovery or had recovered. Getting help early makes a difference.

Substances change the brain areas for reward, stress and self-control. That makes stopping hard without support. Therapy and support help people rebuild their ability to handle cravings.

Shows and posts can make substance use look fun and harmless. Real life often includes health problems, accidents, broken relationships and legal trouble. Plenty of people have a great time without using.

The body often shows the first signs. Some come from the substance itself, and some come from withdrawal as it wears off.

Things you might notice

• Trouble sleeping, shakiness, sweating, nausea or a racing heart as a substance wears off
• Seeming very sleepy, confused, or "nodding off"
• Tiny pupils (with opioids)
• Seeming dazed, slurred speech, chemical smells or paint stains (with inhalants)
• Needing more and more to feel the same effect

As use goes on, the brain’s stress system becomes more sensitive. When the substance wears off, a person can feel irritable, uneasy or anxious.

Things you might notice

• Feeling low or anxious, and using anyway
• Strong cravings that make it hard to think of anything else
• Paranoia or panic (with stimulants or strong cannabis)
• Everyday things no longer feel enjoyable

When substances start to take over, other parts of life often slip. These changes are some of the clearest signs of a substance use disorder.

Things you might notice

• Spending a lot of time using, or getting over it
• Giving up activities that used to matter
• Falling behind at home, school or work
• More arguments with family or friends
• Ending up in risky situations, like driving after using

Naloxone is a nasal spray that can reverse an overdose from opioids, including fentanyl, when it’s given in time. You spray it into one nostril. It can bring back normal breathing within 2 to 3 minutes. With strong opioids like fentanyl, more than one dose may be needed.

Where to get it

• Over the counter in all 50 states, with no prescription
• Pharmacies, and some grocery stores, convenience stores and gas stations
• Free from many community naloxone programs and syringe services programs

It won’t harm someone who is overdosing on something other than opioids, so if you’re unsure, use it and call 911. After giving it, stay with the person until help arrives, or for at least 4 hours.

SAMHSA describes health as overcoming or managing one’s condition or symptoms, and making informed, healthy choices that support physical and emotional well-being.

Small steps that support health

• Regular sleep and meals
• Moving your body in ways you enjoy
• Getting help for stress, anxiety or low mood too
• Talking therapy, like CBT

Having a stable and safe place to live is one of the four main parts of recovery.

A home with fewer triggers can make cravings easier to handle, because places and things linked to past use can set off strong urges.

Purpose means having meaningful daily activities, such as a job, school, volunteering, caring for family, or creative projects. It also means having the independence and resources to take part in society.

Because substances can make everyday rewards feel flat, rebuilding things you care about helps the brain’s reward system find healthy joy again over time.

Ideas to try

• A class or new skill
• Volunteering
• Art, music or writing
• A sport or club

Community means having relationships and social networks that provide support, friendship, love and hope.

Recovery is supported by peers, friends and family members. Peer-led mutual-help groups offer fellowship with people who truly understand.

Places to find community

• SMART Recovery meetings (free, in person or online)
• AA meetings (free to attend)
• Family, friends, clubs or faith groups

CBT helps a person gain control of stressful thoughts and emotions that can lead to wanting to use.

It also helps people notice, avoid and handle situations that make using more likely.

What it can look like

• Mapping your triggers
• Planning what to do when a craving hits
• Practicing new skills between sessions

Also called motivational enhancement therapy, it helps people build their own resolve to change. It does not lecture or push. It works with how ready a person feels right now.

What it can look like

• Talking about what matters most to you
• Weighing the pros and cons of change
• Setting goals you choose yourself

Contingency management gives small incentives, such as prizes or gift cards, for reaching goals like staying substance-free or going to sessions.

It uses the brain’s own reward system in a healthy way. For meth use, it has the strongest evidence of any behavioral treatment.

Family therapy helps people, especially young people, and their families deal with things that affect substance use, and improves how the family works together.

For teens, many helpful approaches involve family members or other caregivers in treatment.

SMART Recovery describes itself as an evidence-informed approach to overcoming addictive behaviors and living a balanced life. Groups are led by trained facilitators, held in person and online, and are free. There are also Family & Friends groups.

AA is a fellowship of people who come together to solve their drinking problem. It is open to anyone who wants to do something about their drinking, and it costs nothing to attend.

Supportive relationships are one of the four pillars of recovery. Families, friends, schools, faith groups and recovery communities can all help someone feel less alone.

How to support someone without judgment

• 🕊️ Pick a calm, private moment, not when they are using or upset
• 👂 Listen without judgment and speak with kindness
• 💬 Share your worry gently, and ask how you can help
• 🌟 Mention their strengths, not only the problems
• 🔁 Repeat back what you heard: "I heard you say…"
• ⏳ Be patient. It may take many conversations
• 🧭 Offer to help them find support, like the National Helpline

Families: parents and caregivers who are involved and supportive help protect young people from substance problems. Family therapy helps families work on the things that affect substance use and improves how the family works together. For teens, many helpful approaches involve family members or caregivers.

Friends: positive relationships are a protective factor, and supportive friends are part of the "community" pillar of recovery.

Ways friends can help

• Check in with a simple "How are you, really?"
• Never leave a friend alone if they have used too much: call 911 if they can’t be woken
• Plan fun things that don’t involve substances
• Respect their choice not to use

Peers: mutual-help groups are peer-led groups that offer fellowship and support. Hearing from someone who has been there can make recovery feel possible. Hope is the foundation of recovery.

Caring about someone who uses substances can be stressful and tiring. Taking care of yourself is part of helping them.

Ways to care for yourself

• Call SAMHSA’s National Helpline: it serves family members too
• Join a group for family and friends, like SMART Recovery Family & Friends (free)
• Keep up your own sleep, meals and hobbies
• Talk to someone you trust about how you feel

Ways communities reduce stigma

• 🗣️ Use person-first words, like "person with a substance use disorder" instead of "addict"
• 🙅 Avoid words like "clean" and "dirty", which can take away hope
• 🎉 Celebrate recovery milestones and stories
• 🚪 Make it easy and safe to ask for help