We all know that adolescence can be a challenging phase, and sometimes teens turn to drugs or alcohol as a coping mechanism. As a parent, it can be scary to consider that your child may be drinking, vaping, or using drugs. Are you aware of the common issues that teens face? While teen mood swings are normal, behavioral and physical changes can be warning signs of drug abuse and addiction. 

Warning Signs of Teen Drug Abuse

Substance use can ripple through many aspects of a teen’s life. When alcohol is combined with other drugs, the risks multiply. Be alert to changes in mood, behavior, appearance, and physical health.

Changes in mood and personality

Drugs and alcohol alter the brain’s chemistry, amplifying some emotions and muting others. A teen may:

  • Withdraw socially or seem depressed

  • Become more hostile, irritable, or defiant

  • Act secretive or lie about where they’ve been

  • Struggle with concentration or focus

Changes in behavior

Drugs can change the way teens act. Drugs cause mood swings, risky behavior, and increased need for privacy, Drug abuse and addiction can make drugs the focus of a person’s life, changing how they interact with friends and family.

Substance use often shifts priorities and patterns. You might see:

  • A decline in grades or new disciplinary issues at school

  • A sudden change in friend groups or pulling away from old friends

  • Late-night outings or disappearing for hours

  • Increased privacy (locked doors, closed social media)

Changes in appearance

Drug use can cause short-term and long-term effects on how someone looks. Over time, a teen on drugs may show noticeable changes in appearance.

Over time, substance use can show in how a teen looks:

  • Red or bloodshot eyes

  • Unexplained bruises, sores, or possible track marks

  • Slurred or rapid speech

  • Poor hygiene, messy appearance, changes in weight

Physical health

Drugs affect the body and can lead to lasting damage. Drugs can have serious short-term and long-term effects.

Drug use can strain the body. Watch for:

  • Frequent colds, flu, or unexplained illnesses

  • Fatigue or sudden energy crashes

  • Nosebleeds (especially with snorted substances)

  • Tremors, shaking, vomiting, or seizures

If you notice several of these signs over weeks or months, it’s wise to dig deeper — not as an accusation, but out of concern.

Dangers of Teen Substance Abuse

Even occasional use can have serious consequences for adolescent health and well-being.

Effects of Drugs on on the Brain

The teenage brain is highly vulnerable to addiction and long-term changes (NIDA, 2024). Risks include:

  • Disruption of brain circuits involved in reward and memory

  • Reduced ability to feel natural pleasure

  • Impaired memory and decision-making

  • Higher likelihood of depression, anxiety, or psychosis

Teens who begin drinking or using drugs early are also more likely to develop substance use disorders later in life (NIDA, 2024).

Poor Impulse Control

Drinking alcohol and using drugs can encourage to poor decision-making, leading to:

  • Car accidents
  • Criminal records
  • Unprotected sex
  • Damaged relationships with friends or family members

If you have any reason to suspect your teen is using drugs or drinking alcohol, don’t be afraid to err on the side of caution and have a talk with your teen. Prepare to take action by getting information to talk with your teen about drugs and their effects.

Learn About Teen Substance Abuse with Parent Wise

Our online Parent Wise course helps you build awareness about teen issues like alcohol and drugs, as well as the positive parenting skills to have meaningful conversations with your teen. 

In Parent Wise, you’ll learn about:

  • Underage drinking 
  • Nicotine
  • Marijuana
  • Prescription drug misuse
  • Motives for substance abuse
  • Social pressures

You’ll also learn related skills that can help you and your child respond effectively to substance abuse: 

  • Healthy coping skills
  • Building self-esteem and connecting with values
  • Dealing with peer pressure
  • Communication skills for effective expression
  • Setting boundaries
  • Developing positive relationships
  • Active listening

Here’s what parents had to say about our substance abuse resource:

“The course was good and informative. It gives me a reason to start a discussion about drug and alcohol use. I learned some new things and was reminded of others.”

“This course was amazing. I wish I would have had this course when my oldest daughter was a teen and experimenting with alcohol and prescription drugs.”

Take action and get informed about substance abuse.
Enroll in Parent Wise today! 

Who is This Course For?
  • Parents of teens who are going through teen issues
  • Parents of pre-teens or teens who want to learn more to prevent teen issues
  • Family members or other adults who want to be aware and there for a teen in their life

3rd Millennium Classrooms is a prevention education provider to middle and high schools nationwide.
Learn more by visiting 3rdmil.com.