A new understanding of addiction will make it easier to reduce drug abuse in the years ahead, according to the director of the National Institute on Drug Abuse.
Major scientific advances have revolutionized our understanding of drug abuse and addiction, and this new knowledge has the potential to reduce the United States' drug abuse burden significantly in the twenty-first century. We now know that drug abuse is essentially a brain disease and should be addressed as such. It is not just a social problem or a moral failing on the part of addicts. It is important to state at the onset, however, that an individual's life decisions do play major roles both in the initial choice to use drugs and during the recovery process.
Drug abuse affects nearly everyone in the United States either directly or indirectly. A recent study estimated that drug abuse and addiction cost the U.S. public more than $110 billion per year. Improved prevention and treatment are the best ways to reduce that cost. However, when it comes to making policy decisions about drug abuse, there is a wide gap between the scientific facts and public perception.
The most beneficent public view of drug addicts is as victims of their societal situation. However, the more common view is that drug addicts are weak or bad people, unwilling to lead moral lives and to control their behavior and gratifications. There are many people who believe that addicted individuals do not even deserve treatment. This stigma, and the underlying moralistic tone, affects all public-policy decisions about drug use and drug users.
We can make real progress in controlling drug abuse and addiction, but we must first replace ideology with science.
The Facts About Addiction
Neuroscience research has begun to reveal that the addicted brain is distinctly different from the non-addicted brain. It has also revealed to us some common elements of addiction, regardless of the substance being used. Researchers also better understand the biochemical reactions whereby drugs work their effects on the brain and body.
A variety of studies have shown that genetic differences can make a person more or less likely to become addicted. A recent study provides an interesting example. The study showed that people with a gene variant in an enzyme known as CYP2A6 tend to metabolize nicotine more slowly. These people are less likely to become addicted to nicotine than people without the variant, and, if they do become tobacco-dependent, they smoke fewer cigarettes.
In addition, advanced biological techniques have allowed us to identify the major receptors for virtually every drug of abuse. Receptors are "docking ports" on the surface of brain cells where molecules of a particular drug can attach and affect the cell. New techniques have taken our understanding of these drug receptors to the next level: We now know how they work in great detail and understand how their mechanisms affect behavior and brain function.
In the past few years, we have been able to create genetically altered "knockout" mice, which lack one or more of these receptors. Studies of the drug-responsiveness and behavior of these mice have illuminated the complexity and the interconnectedness of the brain mechanisms that underlie addiction. For example, experiments with these knockout mice have demonstrated that the pleasurable effects of cocaine remain despite the absence of the dopamine transporter, a molecule previously thought to be the primary mediator of these effects.
A number of studies have also highlighted some common elements of addiction. For example, virtually every addictive drug - be it cocaine, marijuana, methamphetamine, heroin, or nicotine - appears to increase the levels of dopamine, a substance found in a brain area responsible for creating the sensation of pleasure.
This brain area, the mesolimbic reward system, is responsible for the initial experiences of pleasure following drug use, and its activation appears to reinforce drug-taking behavior. …