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Figure 2
The slope of the line indicates how quickly the level of the drug—in
this case, alcohol—is rising in the brain. And the faster the rise, the
more dopamine release, the more euphoria, and the more craving
down the road.
That’s why smoking crack is more appealing than snorting pow-
der cocaine: smoking produces a faster, larger dopamine rush. Regu-
lar cocaine can’t be smoked; the heat destroys it. Transforming it into
crack makes it smokable, so the drug gets in the body through the lungs
instead of the nose. That makes a big difference.
When powdered cocaine flies up into the nose, it lands on the nasal
mucosa, the red lining inside your nose. It’s red because the blood ves-
sels are at the surface. Cocaine enters the bloodstream through these
vessels, but it’s not very efficient; there isn’t much room available in
there. Sometimes when a user snorts a line of cocaine, some of the
powder never makes it into their system because there’s not enough
space for it on the surface of the mucosa.
That’s not to say that snorting cocaine isn’t dangerous and addictive,
but there’s a way to make it even more dangerous and more addictive:
smoking it. Smoking cocaine as crack makes the process more efficient.
Unlike the nasal mucosa, the surface area of the lungs is huge. Filled
with hundreds of millions of tiny air sacs, the surface area is equal to
42
THE MOLECULE OF MORE
one side of a tennis court. There’s plenty of room there, and when the
vaporized cocaine hits the lungs, it goes right into the bloodstream and
up to the brain. It’s a steep slope—a sudden burst—and a big hit to the
dopamine system.
The link between a rapidly rising blood level and dopamine release
is also why addicts progress to injecting drugs into their veins. Other
routes of administration no longer give them the thrill they’re after.
Injecting drugs is scary, though, and is a clear sign of an addict, so the
stigma and fear of the needle may stop many of them from progressing
further. Unfortunately, smoking gets the drug into the brain about as
fast as intravenous injection. Smoking also lacks the stigma associated
with needles. As a result, many would-be casual users of cocaine pro-
gress to life-destroying addiction. The same thing happened with meth-
amphetamine when it became available in smokable form.
DRUNK VERSUS HIGH:
WHAT’S THE DIFFERENCE?
There’s a big difference between being high and being drunk,
but not everyone knows that. Even fewer understand why.
An evening of drinking feels best at the start. The level
of alcohol is rising rapidly, and that feels good—it’s
dopa-
minergic euphoria
, directly related to how fast the alcohol
gets into the brain. As the night goes on, though, the rate
of increase slows down, and dopamine turns off. Euphoria
gives way to drunkenness. The early stage of rising levels of
alcohol might be characterized by increased energy, excite-
ment, and pleasure. Intoxication, on the other hand, is char-
acterized by sedation, poor coordination, slurred speech,
and bad judgment. The speed with which alcohol gets into
the brain determines how high a drinker feels. It’s the total
amount of alcohol consumed, regardless of whether it’s fast
or slow, that determines the level of intoxication.
43
DRUGS
Inexperienced drinkers get the two confused. They start
drinking, push their blood alcohol level up, and experience
the pleasures of dopamine release, then mistakenly believe
that the pleasure is the pleasure of intoxication. So they
keep drinking more and more, trying in vain to get the rush
back. It ends badly, often bent over a toilet.
Some people figure this out on their own. A woman seen
at a cocktail party said she always had more fun with mixed
drinks than with beer. At first this appeared to be nonsense,
because alcohol is alcohol whether it comes from a beer
or a daiquiri. But science validates the woman’s experience.
A mixed drink is more concentrated, and it’s usually sweet-
ened with sugar, so people tend to drink it faster. Mixed
drinks usually contain more alcohol than beer or wine.
Therefore a mixed drink delivers a lot of alcohol fast, a burst
of dopaminergic stimulation, as opposed to an evening of
slowly increasing intoxication. This woman wanted elation,
not inebriation, so of course the mixed drinks let her have
a better time. She was getting a dopamine hit from a few
cocktails that an evening of many beers couldn’t deliver.
THE CRAVING THAT NEVER STOPS
Although craving never stops as long as an addict keeps using drugs, the
brain gradually loses its ability to deliver the high—the desire circuit
simply reacts less and less, so much so that they might as well replace
the drug with salt water.
1
1 When scientists injected long-time cocaine users with a stimulant similar to cocaine,
they released 80 percent less dopamine than healthy people given the same drug.
The dopamine released by the addicts was about the same amount that the scien-
tists saw when they injected a placebo—an inactive substance, such as salt water.
44
THE MOLECULE OF MORE
Patrick Kennedy, the former U.S. representative for Rhode Island’s
1st Congressional District, and son of the late Massachusetts senator
Ted Kennedy, understands the diminishing stimulation of drug use.
Arguably the foremost advocate for brain research and improved men-
tal health services in the United States, he himself struggled with addic-
tions and mental illness, publicly acknowledging his problems after he
drove into a barricade at the U.S. Capitol in the middle of the night.
In a 60 Minutes interview with Lesley Stahl he spoke of the need to use,
even in the absence of pleasure.
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