Cocaine is a highly addictive substance. People who take it can become physically and psychologically dependant upon it to the point where they can't control their cravings. Researchers have found that cocaine-addicted monkeys will press a bar more than 12,000 times to get a single dose of it. As soon as they get it, they will start pressing the bar for more.
Crack and other addictive drugs chemically alter a part of the brain called the reward system. As mentioned previously, when people smoke crack, the drug traps the chemical dopamine in the spaces between nerve cells. Dopamine creates the feelings of pleasure we get from enjoyable activities such as eating and having sex. But in crack users, dopamine keeps stimulating those cells, creating a "high" -- a euphoric feeling that lasts anywhere from five to 15 minutes. But then the drug begins to wear off, leaving the person feeling let-down and depressed, resulting in a desire to smoke more crack in order to feel good again.
The brain responds to the dopamine overload of the crack high by either destroying some of it, making less of it or shutting down its receptors. The result is that, after taking the drug for a while, crack users become less sensitive to it and find that they must take more and more of it to achieve the desired effect. Eventually, they cannot stop taking the drug because their brains have been "rewired" -- they actually need it in order to function. How long does it take to become addicted? That varies from person to person, and an exact number is difficult to pin down, especially when physical addiction is paired with psychological addition.
Of course, not everyone reacts the same way to extended use. Some users actually become more sensitive to crack as they take it. Some people die after taking a very small amount because of this increased sensitization.
When an addicted person stops taking crack, there is a "crash." He or she experiences the symptoms of withdrawal, including:
- Intense cravings for the drug
In the next section, we'll discuss just how widespread this particular addiction is.