COCAINE VS. METHAMPHETAMINE

In the 2004 movie "Alien vs. Predator," teens (mostly) witnessed
these film-favorite monsters in mortal combat, only to be stymied by
a young (female, in this case) human scientist's raw determination
and instinctual savvy.

While preparing for this column, in a bit of a mind-wandering
fantasy, I somehow imagined that the part of the Alien could be
played, metaphorically speaking, by the drug cocaine (it comes mostly
from outside the United States), while the part of the Predator could
go to methamphetamine (made by local drug pushers). Our hero is UCLA
neuroscientist and addiction researcher Thomas F. Newton, with a
strong supporting, albeit all-male, cast research team.

I'm sticking with the monster metaphor for good reason: surveys show
that both methamphetamine and cocaine have a strong foothold on
American users, especially teens. These drugs are destroying lives at
this very moment. While less than 1 percent of teens have tried
methamphetamine, nearly half of those are recent users, according to
the National Survey on Drug Use and Health, released last month.
About 2 million Americans 12 years and older are regular cocaine
users, about one-fourth of them using the much more highly addictive
form known as crack.

Based on the presumptive similarities between the cocaine and
methamphetamine molecules and the fact that both are stimulants and
utilize the dopamine (pleasure) circuitry -- with some exceptions --
scientists have tended to think of their effects as somewhat alike.
In the article "Cocaine and Methamphetamine Produce Different
Patterns of Subjective and Cardiovascular Effects," recently
published in the journal Pharmacology, Biochemistry and Behavior,
Drs. Newton and colleagues share the results of a controlled study
conducted at the Jane and Terry Semel Institute for Neuroscience and
Human Behavior at UCLA.

Newton et al found that, although both drugs are stimulants, cocaine
and methamphetamine have distinctive patterns of subjective and
cardiovascular arousal. The subjective effects of cocaine tend to
peak and also tend to decline more rapidly than those caused by
methamphetamine, whose subjective effects tend to rise more slowly
and are more sustained than that of cocaine.

Also, the cardiovascular effects (heart rate and blood pressure) of
both drugs were found to have similar initial patterns, but
methamphetamine?s effects last longer.

I asked Dr. Newton to comment on the usefulness of this research.

"The significance of this study," he said, "is that it shows that
drugs that we thought worked more or less alike actually produce
quite different effects."

Newton added, "It underscores the importance of developing treatment
aimed at specific medications as opposed to addiction generally."

There are a lot of reasons why researchers and clinicians would want
to know this kind of information. One would be to explain reported
differences in drug-taking patterns among cocaine and methamphetamine users.

The former, cocaine users, tend to binge, while methamphetamine users
are more likely to consume on a daily basis, Newton writes. In this
study, he points out that factors such as differences in drug
half-life (the time it takes for one-half of the drug taken to be
neutralized by the body) can make a difference.

"For example," he says, "the effects of cocaine are pretty much gone
in 20 minutes to a half hour at the longest, whereas the half-life of
cocaine is 90 minutes at the shortest, which means that you have 80
percent of your blood level when your subjective effects have gone
completely away. How that works is really not known."

"Another important significance of the study," he said, "is that the
effects of methamphetamine lasted longer than we expected, compared
to what we saw for cocaine. Why these two drugs differ, on a
molecular level, is really not clear."

With each gain in knowledge, we can only hope that, somehow, there
can be a parallel gain in lives saved and the quality of lives lived.

Allan J. Comeau, Ph.D., is a psychologist on the clinical faculty at
UCLA and a former president of the Inland Southern California
Psychological Association. Write him at 2001 S. Barrington Ave.,
Suite 304, Los Angeles, CA 90025, or visit
(http://www.drcomeau.com)www.drcomeau.com