Addiction is a disease that gets worse if it’s not treated. Drug addiction causes your brain to change and drives you to keep using the drug, even if it leads to bad outcomes.
Marijuana addiction is more common among teens than adults because teen brains are still developing and are more vulnerable to damage from chemicals than adult brains. Your brain doesn’t stop developing until your mid-20s. If you start using marijuana before age 14, you’re more likely to become addicted by the time you’re an adult.