Cocaine Causes So
Many Strokes and Heart Attacks
(HealthScoutNews) -- Scientists have known for a long time that
cocaine use could cause blood pressure to rise, sometimes so much
so that a stroke or heart attack would occur.
Researchers believed this was because blood vessels contracted after
a person sniffed cocaine. But new research has now demonstrated
that blood vessels also expand in an effort to reduce skyrocketing
blood pressure. This makes the heart beat too rapidly, and the body's
efforts to counteract the rapid blood pressure spike fail.
The findings may help scientists develop new drugs to treat
cocaine abusers who land in emergency rooms, according to the
study's co-author, Dr. Meryem Tuncel, a researcher at the University
of Texas Southwestern Medical Center.
"I don't think the public is very aware that they can die
suddenly from cocaine because of increases in blood pressure,"
Tuncel said. "They should know that they can die easily."
Cocaine reportedly causes more deaths than any other illegal
drug, and it's estimated to be responsible for 30 percent of all
drug-related visits to emergency rooms in the United States.
Researchers have estimated that the risk of a heart attack jumps
by 24 times in the hour after a person uses cocaine.
Doctors have long known that cocaine causes heart attack and
stroke, especially in regular users, said Ronald Herning, a research
psychologist with the National Institute on Drug Abuse.
"It probably weakens blood vessels," he added. "The
increasing heart rate and blood pressure wears them out."
Experts thought that the effects of cocaine made blood vessels
shrink, causing higher blood pressure, just as squeezing a garden
hose causes water pressure to rise. But they based their theories
on tests done on animals, Tuncel said.
However, the researchers at the University of Texas gave doses
of cocaine to 15 male volunteers who said they had never taken
the drug before. The men received the drug through nasal drops
and, separately, through injection in the arm.
The doses were "very small," Tuncel said. "There's
no euphoric effect. We cannot give larger doses because of ethical
The blood vessels did constrict in the men who received cocaine
through injection into the blood stream. But when they received
cocaine through the nose, the blood vessels actually became larger,
allowing more blood through.
Enlarged blood vessels would normally cause lower blood pressure.
But the researchers suspect that rapid heartbeats kept blood pressure
high, much like turning up a faucet increases water pressure in
that garden hose.
"The important mechanism is what's happening in the brain,"
Tuncel said. "The brain is telling the heart to pump harder."
The body's reaction to the negative effects of cocaine actually
prevents the drug from doing more damage, according to Dr. Murray
Mittleman of the Institute for Prevention of Cardiovascular Disease
at Beth Israel Deaconess Medical Center in Boston.
"Without (the expansion of blood vessels), we'd see much
worse consequences than what we already see," Mittleman said.
Tuncel and Mittleman agreed that the findings, which appear
in this week's issue of the journal Circulation, may lead
to better treatments for cocaine users who suffer from heart problems.
What To Do
UK online offers information, support and a self-test to
The U.S. National
Institute on Drug Abuse has more information about cocaine,
including a Research
Report on Cocaine Abuse and Addiction.
Reference Source 101