The science of neurology has created a paradigm shift in our basic understanding of the structure of the brain and the rest of the human nervous system. It has taken a long time, and a large group of doctors, clinicians and assorted scientists to piece together the ways in which this new knowledge of the brain has direct application to the states of mind and body we call addiction, alcoholism, or drug dependence.

When I first began following the subject of addiction in the early 1990s, the addiction field was still small, the insights highly tentative. However, what I had originally viewed as a series of potential breakthroughs in addiction research very rapidly became the tip of an enormous iceberg: brain science, and the revolutionary new directions represented by modern biology. The Chemical Carousel, my book on addiction research, is a snapshot in time of an extremely fast-moving landscape.

Herewith, a few random samplings:

— As many as 30 percent of suicides every year may come from the nation’s pool of about 22 million alcoholics. Half of all emergency room patients with multiple fractures are alcoholics, according to research by prominent alcohol investigator George Vaillant. Female alcoholics develop liver diseases like cirrhosis more frequently than men do. 10 percent of the nation’s drinkers consume 50 percent of the alcohol purchased in America. Alcohol loses most its rewarding properties when brain receptors for opiates are blocked.

— Large numbers of addicted cigarette smokers suffer from clinical depression. Smoking a single cigarette has been likened by one nicotine researcher to “lighting a match in a gasoline factory.” Women who smoke more than 20 cigarettes a day face an 80 per cent greater risk of developing breast cancer, compared to non-smoking women. Roughly one out of every three women of childbearing age was a cigarette smoker in 1991. Former Surgeon General Everett Koop said tobacco smoking results in “a thousand funerals a day.”

— Large doses of methamphetamine can trigger psychotic episodes indistinguishable from schizophrenia. Vigabatrin, a drug for the treatment of epilepsy, may turn out to be the first government-approved treatment for meth addiction.

— Recent studies have documented the existence of severe caffeine addicts, who suffer significant depression and impaired cognition for several months following termination of coffee drinking.

— Mice that have been genetic altered so that they lack the ability to taste sweet foods still prefer sugar water to regular water. And PET scans of former bulimics (men suffer from it, too) disclosed that they showed a marked decrease in serotonin binding at 5HT receptors, compared to healthy, age-matched women.

— Between 3 and 7 percent of Americans are “poor metabolizers” due to a genetic variant for the enzyme CYP2D6. For them, the recommended drug dosage can be far too high.

— Notably, while there is little evidence in animal models for marijuana tolerance and dependence — the class determinants of addiction — a significant percentage of regular marijuana users report that they suffer from severe withdrawal symptoms when they abstain completely from pot. What has emerged in the past ten years is a profile of marijuana withdrawal, where none existed before. The syndrome is marked by irritability, restlessness, generalized anxiety, hostility, depression, difficulty sleeping, excessive sweating, loose stools, and loss of appetite. Many abstaining pot smokers complain of feeling like they have a low-grade flu, and they describe a psychological state of existential uncertainty — “inner unrest,” as one researcher calls it.

This is a finding I will pursue in the next post. I own and maintain the Addiction Inbox blog, and the amount of evidence posted there about marijuana withdrawal makes it a fascinating and controversial topic.

References

Hanson, Dirk. The Chemical Carousel: What Science Tells Us About Beating Addiction. North Charleston, SC: BookSurge Publishing, 2009.

The Chemical Carousel is an in-depth look at addiction science and medical treatments for drug dependence and alcoholism. An experienced science and business journalist, author Hanson brings a complex and widely misunderstood subject out of the shadows and into the light of understanding. In this groundbreaking and highly readable examination of addiction science and the biological, emotional, and scientific underpinnings of substance abuse, The Chemical Carousel breaks through the myths, while presenting the surprising and cutting-edge facts about addiction and its medical origins. Hanson leaves no stone unturned in this invaluable examination of why people become addicted.

— From the Publisher: Booksurge Publishing

Kreek, M., LaForge, K., & Butelman, E. (2002). Pharmacotherapy of addictions Nature Reviews Drug Discovery, 1 (9), 710-726 DOI: 10.1038/nrd897

Leshner, A. (1997). Addiction Is a Brain Disease, and It Matters Science, 278 (5335), 45-47 DOI: 10.1126/science.278.5335.45

Miller, William, and Kathleen, Carroll, Eds. Rethinking Substance Abuse:
What the Science Shows, and What We Should do About it. New York: The Guilford Press, 2006.

National Center on Addiction and Substance Abuse at Columbia University. Women under the Influence. Baltimore: The Johns Hopkins University Press, 2006.

Vaillant, G. E., The Natural History of Alcoholism Revisited. Cambridge: Harvard University Press, 1995.