(National Institute on Drug Abuse) We’ve described before how drugs can change the way the brain’s “reward system” works, so that a person has to use more of a drug to get the same high they experienced the first time. It also makes them less able to enjoy other things that used to make them feel good—like friends, food, sports, and other activities.

That’s only part of the drugs-and-brain story, though.

Downward spiral

With drug use, other brain changes occur that lead a person to feel depressed and anxious. 

Read the rest on NIDA's Drugs and Health blog.