Cocaine use in warm environments impairs body's cooling mechanisms -- and can be lethal

June 03, 2002

DALLAS - June 4, 2002 - Cocaine, even in small amounts, can be fatal when taken in warm environments, such as hot weather, crowded nightclubs or rave parties - all-night dance parties where illicit cocaine use is common - according to researchers at UT Southwestern Medical Center at Dallas.

The researchers discovered that cocaine elevates body temperature by impairing the body's ability to increase skin-blood flow, to sweat and to perceive excessive heat stress. The findings appear in today's issue of Annals of Internal Medicine.

"Individuals who abuse cocaine, especially in hot temperatures while participating in recreational sports or attending rave parties, won't perceive that they are hot and are, therefore, less likely to drink water or to find cooler conditions," said Dr. Craig Crandall, assistant professor of internal medicine and lead author of the study. "The hyperthermic effects of cocaine are greatly amplified when the drug is used under these conditions.

"This may result in serious heat-related injuries, including heat cramps, heat exhaustion, heat stroke and ultimately death," added Crandall, who is also a research scientist at the Institute for Exercise and Environmental Medicine, a joint venture between UT Southwestern and Presbyterian Hospital of Dallas.

Crandall and his collaborators studied the mechanism of cocaine-induced hyperthermia in seven volunteers who had never used cocaine. The researchers compared the effects of a small dose of cocaine dissolved in saline solution and a placebo. Both were applied to the inside of the nose of each of the study volunteers in separate trials. The researchers measured esophageal temperature, skin-blood flow, sweat rate and perceived thermal sensation.

Approximately 25 million Americans have tried cocaine, which is a major cause of life-threatening cardiovascular emergencies, including hypertensive crisis, acute myocardial infarction and ventricular arrhythmias. Cocaine is the most frequent cause of drug-related deaths reported by medical examiners, and it is the most commonly used illegal drug among people seeking care in hospital emergency departments or drug treatment centers.

"The lethal effect of cocaine is unique among those of other illicit drugs because it is related not only to dose but also to the drug's tendency to cause hyperthermia, which increases the risk for death," Crandall said. "The traditional view is that cocaine increases activity levels resulting in increased heat production; however, we found that in addition to causing increased heat production, impaired heat dissipation is another major mechanism by which cocaine elevates body temperature in humans.

"Identifying the precise molecular mechanisms of cocaine-induced hyperthermia could lead to the identification of new drug targets that may reduce cocaine-related deaths."
-end-
Other researchers included Dr. Ron Victor, chief of hypertension, and Dr. Wanpen Vongpatanasin, assistant professor of internal medicine.

The study was funded by the National Institutes of Health, the American Heart Association and the National Institute on Drug Abuse.

To automatically receive news releases from UT Southwestern via e-mail, send a message to UTSWNEWS-REQUEST@listserv.swmed.edu. Leave the subject line blank and in the text box, type SUB UTSWNEWS

UT Southwestern Medical Center

Related Cocaine Articles from Brightsurf:

Sleep-deprived mice find cocaine more rewarding
Sleep deprivation may pave the way to cocaine addiction. Too-little sleep can increase the rewarding properties of cocaine, according to new research in mice published in eNeuro.

Nucleus accumbens recruited by cocaine, sugar are different
In a study using genetically modified mice, a University of Wyoming faculty member found that the nucleus accumbens recruited by cocaine use are largely distinct from nucleus accumbens recruited by sucrose, or table sugar.

Astrocytes build synapses after cocaine use in mice
Drugs of abuse, like cocaine, are so addictive due in part to their cellular interaction, creating strong cellular memories in the brain that promote compulsive behaviors.

Of all professions, construction workers most likely to use opioids and cocaine
Construction workers are more likely to use drugs than workers in other professions, finds a study by the Center for Drug Use and HIV/HCV Research (CDUHR) at NYU College of Global Public Health.

Chronic cocaine use modifies gene expression
Chronic cocaine use changes gene expression in the hippocampus, according to research in mice recently published in JNeurosci.

Blocking dopamine weakens effects of cocaine
Blocking dopamine receptors in different regions of the amygdala reduces drug seeking and taking behavior with varying longevity, according to research in rats published in eNeuro.

Born to run: just not on cocaine
A study finds a surprising response to cocaine in a novel strain of mutant mice -- they failed to show hyperactivity seen in normal mice when given cocaine and didn't run around.

Cocaine adulterant may cause brain damage
People who regularly take cocaine cut with the animal anti-worming agent levamisole demonstrate impaired cognitive performance and a thinned prefrontal cortex.

Setting affects pleasure of heroin and cocaine
Drug users show substance-specific differences in the rewarding effects of heroin versus cocaine depending on where they use the drugs, according to a study published in JNeurosci.

One in 10 people have traces of cocaine or heroin on their fingerprints
Scientists have found that drugs are now so prevalent that 13 percent of those taking part in a test were found to have traces of class A drugs on their fingerprints -- despite never using them.

Read More: Cocaine News and Cocaine Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.