Drug abuse is a serious problem. Recent estimates state that about 6 percent of the American population abuses drugs in some form or other. The abuse of drugs, including alcohol and nicotine, costs the nation more than $275 billion a year.

From Abuse to Addiction

If drug abuse continues long enough, it can produce alterations in the chemical state and the structure of the brain, resulting in a true brain disorder. This disorder in turn lead to drug addiction. This is defined as having lost control over drug taking, even when it is clear that there are detrimental physical, psychological and/or social effects resulting from the drug use.

For what reason?

The reason for abusing drugs is quite simple, it produces feelings of pleasure or removes feelings of stress or emotional pain. It has been shown that nearly all drugs act on the brain reward system, a specific network of neurons that produces feelings of pleasure. Normally, this circuit is involved in a type of learning that helps us survive, since it is activated when we are performing functions essential for survival, such as eating and drinking. The pleasurable feeling ‘teach’ us that it is a good thing and stimulates us to repeat it. Since drugs also activate thus system, people want to repeat the drug use, since it feel pleasurable.

How do They do It?

Neurons communicate with each other through special messengers, called neurotransmitters. Drugs alter the way these messengers carry their message from one neuron to the next. Some mimic neurotransmitters, while others block them. And some change the way neurotransmitters are released or inactivated. Through this change in the chemical messages, drugs inappropriately activate the reward system.

Recently, it has been discovered that there are other factors that influence the risk to get addicted as well.

• Motivation: People who use drugs to get high may get addicted, people who use them for medicinal purposes rarely do.
• Genetic susceptibility and environmental factors: Susceptibility to stress, induced by the environment, also influences the way one responds to drugs.
• Tolerance: The progressive need for an increasing dose varies among people.
• Dependence: The physiological state that causes withdrawal symptoms and leads to the feeling that one can’t live without drugs also differs among individuals.

Through understanding and researching these different factors, scientists hope to get a more complete view on what addiction really is and how it works, which will hopefully lead to new and effective therapies.