We experience pleasure when we do things like shop, score a goal, laugh with friends; or when we consume food or drugs. These are just examples. What makes you feel pleasure? When we feel pleasure our brains release a chemical called dopamine. Dopamine is released for a purpose. It tells the brain to pay attention because this is awesome and we want to remember how great this feels. In the case of scoring a soccer goal, you may remember the move you made for future reference. You will also remember how great it felt and therefore you’ll be more motivated to try again.

Simply put, dopamine helps us remember, learn and feel great. 

Then drugs mess it all up. Dopamine (and other important chemicals) are released in intense amounts and that chemical dump causes a chain reaction of bad things….

First, The body already makes dopamine so the dumping interferes with natural production: So when your body receives so much dopamine (for example, from a drug like heroin or pot) it says to itself, oh, well, since it’s coming from that stuff, I don’t need to make any more of this. So it makes less dopamine and relies, instead, on outside sources for it. Hello addiction. In other words, long-term heavy marijuana usage could reduce your levels of naturally occurring dopamine. Low dopamine levels are associated with issues such as depression, fatigue, and mood changes.

When the body produces less dopamine, the pleasure a person once got from eating ice cream with his best friend while watching America’s Got Talent is no where near what it used to be. The brain has started to rely on the drugs to dump the dopamine. So things that you once loved to do are just not pleasurable any more. You need drugs to feel pleasure. Can you say “addiction?”.

Second, that big dump of dopamine powerfully links together pleasure and drug use, driving the brain to want to do it again, and again, and again—the HABIT formation part of addiction. This is why you do not want the chemical dump from drugs.