March 17, 2005

Immune System May Help Fuel ‘Meth’ Binges

Increasing tolerance for the drug means users need more to stay high, study finds

HealthDay News -- One hallmark of the current surge in crystal meth (methamphetamine) use across the United States is that users often go on extended, drug-fueled binges.

Now, animal studies suggest the body's immune system boosts tolerance to methamphetamine, or "speed," via a vaccine-like mechanism, encouraging these hours-long bouts.

If confirmed in human studies, the findings might help in the development of new treatments for addiction to methamphetamine, which goes by many other street names, including "chalk" and "ice."

"Test animals injected with methamphetamine actually developed antibodies to the drug, which is highly unique for a molecule of its relatively small size," study co-leader Kim Janda, a chemist at The Scripps Research Institute, in La Jolla, Calif., said in a prepared statement.

It's normal for the immune system to develop antibodies to potentially dangerous invaders such as viruses and bacteria; in fact, this reaction is the basis for vaccines. But in people who abuse methamphetamine, this immune system response may enable people to build up antibodies to the drug.

That means they require increasing amounts of the drug to get high, resulting in binge behavior, Janda explained.

"Without knowing it, they're essentially vaccinating themselves against the drug, and that's not a good thing as it requires more of the drug to get high," he said.

The study was presented Tuesday at the national meeting of the American Chemical Society, in San Diego.

More information

The Scripps Research Institute

American Chemical Society

The U.S. National Institute on Drug Abuse has more about methamphetamine.