The Chemistry of Addiction

Until Jr. High, Jane was almost a model student. Her only fault, if you could call it that, was that she was outgoing and liked to “share” a bit too much in class. She was clearly bright, and made all A’s without much effort. Today, Jane is a senior in high school (barely), struggling to graduate, and due to appear in Juvenile Court sometime in November.

She was originally arrested for possession of cocaine, found guilty and sentenced to probation and community service. While she was on probation however, she was cited again for under age drinking and (I know you’re going to find this hard to believe) possession of cocaine.

How can someone so smart be making such bad choices? We like to think that we have some choice in the matter of substance abuse, and of course we do, but some of us may be doomed with less choice than we think. Some of us may actually have brains that sabotage us more easily than the brains of others.

Here’s what happens when we take a drug. There is a tiny space, called the synapse, or synaptic gap, between the end of one neuron and the beginning of the next neuron all throughout our bodies. And did you know that neurons communicate with each other by sending chemical messengers across this gap? There are a number of these messengers, called neurotransmitters. When someone uses Heroin, it rushes across the synapse and binds with endorphin receptor site. When we drink alcohol, it binds to the receptors for acetylcholine, serotonin and GABA. (To see a really cool graphic of this go to But today, let’s focus on the neurotransmitter Dopamine. Dopamine is naturally released by rewarding experiences such as food and sex, and other good stuff associated with the pleasure system of the brain. So of course we all like a little Dopamine! When Jane uses cocaine, it helps the Dopamine stay in the synapse longer, which increases her feelings of euphoria. But here’s the bad news, if Jane uses too much cocaine, the Dopamine pathways are forever altered, and a few hours after using it, there is a decrease in Dopamine levels (no fun), and this decrease can last much longer than the initial increase, so of course, she wants more.

It’s no surprise that people with naturally low Dopamine levels will like drugs such as cocaine. Now Jane may be the only one in her family to use cocaine, but I bet she isn’t the only one with low Dopamine levels. This sort of thing can be inherited, just like eye color. I may be lucky and come from a family with a lot of Dopamine in my synapse to start with, so the desire to do drugs that bind with Dopamine may be limited. Or, I may be genetically predisposed to struggle with a craving to feel better than I naturally do.

Now there is a difference between a desire and a craving. A desire is something we want, and a craving is something we have to have. The craving for drugs by someone who has become addicted is like the craving for food by someone who is starving. She can’t stop until she gets it, and she can’t think of anything else until she gets what her brain chemistry is craving. She may feel remorseful, and she may vow never to do it again, and if it were that easy I wouldn’t be writing this article.

The cognitive, or thinking part of our brain gets cut off, and we are ruled by the primitive part of our brain, the part that craves and doesn’t think too well. Because of this, addicted people often feel a lot of shame. They have the belief that if they just tried harder they could stop drugs, and since they can’t ” just say no” there must be something wrong with them. That’s not true. It would be like telling a hungry person that they were bad because they wanted to eat.

Much can be done to conquer addiction, but in my mind, it all comes down to managing brain chemistry. Aristotle said it well when he said,

“I count him braver who overcomes his desires than him who conquers his enemies; for the hardest victory is the victory over self.”

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