Substance use and teenage mental health

At a glance

Teen substance use can be frightening for parents and carers, but one-off experimentation is different from frequent, hidden or risky use.
Some teenagers experiment because they’re curious, want to fit in, have easy access or are testing independence. Others use substances to deal with anxiety, low mood, trauma, sleep problems or pressure.
The pattern matters: what they’re using, how often, who they’re with, why they’re using it and whether it’s affecting school, relationships, mood or safety.
Try to start with concern rather than anger. Ask what’s going on and keep the conversation open while being clear about rules.
Call 999 or seek urgent medical help if they may have overdosed, can’t be woken, are struggling to breathe, having a seizure, extremely confused or at risk of serious harm. If their use is becoming unsafe or their mental health is getting worse, get outside help quickly².

Substance use can be experimentation, coping or something more serious

New experiences can seem more appealing in adolescence. Teenagers are more sensitive to reward and novelty, while the part of the brain that helps with impulse control and long-term thinking is still developing. In other words, teenagers often know something’s risky – yet find it hard to turn down.

But they don’t all use substances for the same reason. For some, it might be a one-off experiment. Others might try something because friends, family or people online are doing it. Maybe they want to seem older, test their independence or fight boredom – or they simply have easy access to it.

Some are drawn to the sensation itself too: feeling more relaxed, more confident, less inhibited, lighter, detached or less aware of worries for a while.

None of this automatically means they’re addicted or that something’s seriously wrong. But substance use still needs to be addressed. A one-off incident needs a different response from regular use, hidden use, risky use or use that’s clearly linked to distress.

When substance use becomes a way to cope

A very real concern is whether substance use is becoming a way to get through life. A teenager might drink, vape or use drugs to feel less anxious around other people, stop feeling low, block out difficult memories or simply get to sleep.

That can start to affect their choices. Drinking before a party might make socialising seem easier. Cannabis at night might seem like the only way to switch off.

It can also point to something else that needs attention, such as anxiety, low mood, loneliness, bullying, school pressure, family conflict, friendship problems, ADHD or trauma. They could be spending time with a group where substance use is considered normal.

That doesn’t excuse unsafe behaviour. Parents and carers still need to deal with the substance use, but also ask why it’s happening. What are they using? How often? Who are they with? Are they safe? What else might be going on underneath?

Those questions matter because substance use can start to feel like an answer, even when it’s creating more problems: alcohol can make anxiety worse the next day, cannabis can increase paranoia, and stimulants can make panic symptoms worse. This can turn into a pattern:

Something feels difficult, painful or hard to manage.
The substance gives short-term relief.
The relief wears off.
Mood, sleep, anxiety or concentration gets worse.
The teenager becomes more likely to use again next time things feel difficult.

What warning signs to look for

Look for patterns and changes rather than one isolated sign. You might notice:

Increased secrecy
Hidden belongings
Sudden changes in friendship groups
Skipping school or arriving late
Money going missing
A drop in schoolwork
Losing interest in hobbies
More conflict at home
Defensiveness when asked simple questions
Withdrawal from family
Stronger mood swings
Increased anxiety or flatness
Bloodshot eyes
Changes in sleep or appetite
Unusual smells on clothes or in their room
Unexplained tiredness
Seeming intoxicated, spaced out or unusually wired

None of these signs alone prove that a teenager is using substances. But if several things change together, it’s worth taking seriously.

How to talk about it without driving it underground

The first conversation matters. If it becomes a shouting match, a teenager is more likely to deny things or shut the conversation down.

You don’t need to be perfectly calm, but going in with panic or fury usually makes things worse. Start with concern, not accusation. For example:

“I’ve noticed some changes, and I’m worried about you.”

Or:

“I’m not here to shout. I just need to understand what’s going on.”

They might deny it. But avoid direct accusations like calling them a liar, telling them they’re ruining their life, or saying you can’t trust them anymore. Instead, say something like:

“Okay. I’m still worried, and I want you to know I’m here if you need to talk.”

This doesn’t mean you believe everything or drop the issue. You’re keeping the door open.

Boundaries still matter

Understanding why a teenager is using substances doesn’t mean you accept it. Teenagers need clear rules, especially when safety is involved, which could include:

No substances in the home
No getting into cars with anyone who has been drinking or using drugs
Clear rules about parties, sleepovers and where they’re going
Agreeing how they’ll get home safely
Checking in after nights out
Involving school or professionals if use is affecting attendance, behaviour or mental health

Overly harsh punishments can push substance use further underground, but ignoring it isn’t safe either. Be clear about what needs to change, what the rules are and what will happen if those rules are broken.

What to do

Check for immediate danger first

If they may have overdosed, cannot be woken, are struggling to breathe, having a seizure, extremely confused or at risk of serious harm, call 999 or seek urgent medical help.
Stay calm before you speak

Take a moment first. You’re more likely to get an honest answer if you sound worried rather than furious.
Lead with concern

Start with what you’ve noticed and why you’re worried. Keep it specific: sleep, school, mood, money, friends, secrecy or behaviour.
Ask what it's doing for them

Try “What do you like about it?” or “When are you most likely to use it?” This can tell you whether it’s curiosity, peer pressure, anxiety, low mood or something else that’s driving it.
Listen before setting consequences

You still need boundaries, but listening gives you more context and makes it less likely the conversation becomes a battle.
Be clear about safety

Talk about getting home safely, not mixing substances, not being alone if they’re unwell, and knowing when to call for help. Conversations about safety are not the same as you giving permission.
Set calm boundaries

Be clear about what isn’t okay, especially around substances in the home, school, unsafe behaviour, driving, parties or younger siblings.
Look at the wider picture

Ask what else has changed. Are they anxious, low, isolated, under pressure, being bullied or spending time with a new group?
Watch for patterns

A one-off incident is different from something that happens often, is hidden, takes place when they’re alone, is helping them cope, or becoming hard to stop.
Keep doing normal things together

Don’t make every conversation about substances. They still need food, lifts, films, walks, humour and moments where they’re not treated like a problem.
Get support early if needed

A GP, school safeguarding or pastoral lead, therapist or youth substance service can help you understand the level of risk and what support fits.

When to look for further help

It might be time to get extra support around substance use if:

It’s becoming frequent
They’re doing it alone
They’re using it to cope with anxiety, low mood, trauma or sleep
They’ve tried to stop and can’t
They depend on it to relax, sleep, socialise or get through the day
School attendance, behaviour or work is affected
Their mental health’s getting worse
They’re taking greater risks
They’re mixing substances
They’re lying, stealing or becoming unsafe
You’re worried about exploitation or pressure from others
You feel out of your depth

What to remember

Teen substance use can be frightening, but panic rarely helps. Some teenagers experiment and stop. Some need firmer boundaries. Some need help with anxiety, low mood, trauma, peer pressure or dependency. The aim is to understand the pattern, reduce any immediate risk and work out what might be sitting underneath it – while making sure they know they can come to you if they need help.

Footnotes

¹Substance use – a broad term for using alcohol, cannabis, vapes, drugs or other substances that can affect how a young person thinks, behaves, feels or stays safe.

²Advice about drugs, alcohol and support options – parents and carers can speak to a GP, school safeguarding or pastoral lead, local youth substance service, or use trusted services such as FRANK or YoungMinds.