Cannabis use can increase risk of mental health problems. Cannabis can trigger or worsen mental health problems such as anxiety, depression, and psychosis.

The prefrontal cortex is responsible for planning, decision-making, and impulse control. Opioid use can reduce activity in this area of the brain, making it harder for teens to make good decisions and control their impulses.

The hippocampus is a part of the brain that is important for learning and memory. Alcohol can damage the hippocampus, which can lead to problems with learning and memory.

Nicotine can harm the developing adolescent brain. The brain keeps developing until about age 25. Using nicotine in adolescence can harm the parts of the brain that control attention, learning, mood, and impulse control.