“迷幻剂”能提高心率和血压
http://www.100md.com
2000年12月20日
NEW YORK (Reuters Health) - The increasingly popular ``club drug'' ecstasy may increase the risk of cardiovascular complications, researchers report.
In a new study, modest doses of the illegal stimulant ecstasy, or MDMA, increased heart rate, blood pressure and the heart's workload as much as a medication used to stimulate the heart.
The increases in heart rate and blood pressure are similar to what occurs during vigorous exercise, the study's principal investigator, Dr. John Mendelson, of the University of California at San Francisco, told Reuters Health.
, 百拇医药
``Although most people, especially young people, should have no problem with this level of increase in heart rate and blood pressure, anyone with...heart disease could have trouble,'' he said.
The study included eight people who had used ecstasy at least several times in the past. In the first of four weekly sessions, participants received an increasing intravenous dose of the drug dobutamine, which has heart-stimulating effects.
, 百拇医药 During administration of the medication, patients underwent echocardiography, which produces images of the heart in motion.
On three later occasions, the participants received one of two doses of ecstasy or a placebo that did not contain any of the drug.
Heart rate and blood pressure were measured before and after each dose. One hour after receiving the drug or a dummy pill, each person underwent echocardiography.
, 百拇医药
The higher dose of ecstasy (which corresponds to an average dose of the drug) increased heart rate by about 28 beats per minute, the researchers report in the December 19th issue of the journal Annals of Internal Medicine. And blood pressure also increased, with the upper number (systolic pressure) rising by 25 millimeters of mercury (mm Hg) and the lower number (diastolic pressure) rising by 7 mm Hg. The increases in blood pressure and heart rate were similar to those produced by dobutamine.
, 百拇医药
The lower dose of ecstasy did not raise blood pressure or heart rate.
When heart rate and blood pressure rise in natural situations, such as while exercising, the heart becomes more efficient by pumping more forcefully, according to Mendelson. But this did not happen when the participants took ecstasy, he pointed out.
``What this means is that the heart is working harder but with less efficiency,'' Mendelson explained. ``This probably decreases the amount of 'cardiac reserve,' meaning that additional demands on cardiac function may not be met.''
, 百拇医药
He noted that these changes may not have much of an effect on healthy young people, but in older people or those with undiagnosed heart disease, the effect could be ``quite serious.''
In the report, Mendelson and his colleagues note that the testing conditions of the study varied a great deal from how ecstasy is usually taken. They point out that many users take the drug while dancing in hot, crowded nightclubs, and they may take more than one dose or drink or take other drugs at the same time.
, 百拇医药
In addition, the effects of the drug may be different in people with cardiovascular disease than in the people in the study, who were all healthy.
In his remarks to Reuters Health, Mendelson commented that physical activity like dancing may compensate for the lack of ecstasy's effect on the heart's efficiency.
SOURCE: Annals of Internal Medicine 2000;133:969-973., 百拇医药
In a new study, modest doses of the illegal stimulant ecstasy, or MDMA, increased heart rate, blood pressure and the heart's workload as much as a medication used to stimulate the heart.
The increases in heart rate and blood pressure are similar to what occurs during vigorous exercise, the study's principal investigator, Dr. John Mendelson, of the University of California at San Francisco, told Reuters Health.
, 百拇医药
``Although most people, especially young people, should have no problem with this level of increase in heart rate and blood pressure, anyone with...heart disease could have trouble,'' he said.
The study included eight people who had used ecstasy at least several times in the past. In the first of four weekly sessions, participants received an increasing intravenous dose of the drug dobutamine, which has heart-stimulating effects.
, 百拇医药 During administration of the medication, patients underwent echocardiography, which produces images of the heart in motion.
On three later occasions, the participants received one of two doses of ecstasy or a placebo that did not contain any of the drug.
Heart rate and blood pressure were measured before and after each dose. One hour after receiving the drug or a dummy pill, each person underwent echocardiography.
, 百拇医药
The higher dose of ecstasy (which corresponds to an average dose of the drug) increased heart rate by about 28 beats per minute, the researchers report in the December 19th issue of the journal Annals of Internal Medicine. And blood pressure also increased, with the upper number (systolic pressure) rising by 25 millimeters of mercury (mm Hg) and the lower number (diastolic pressure) rising by 7 mm Hg. The increases in blood pressure and heart rate were similar to those produced by dobutamine.
, 百拇医药
The lower dose of ecstasy did not raise blood pressure or heart rate.
When heart rate and blood pressure rise in natural situations, such as while exercising, the heart becomes more efficient by pumping more forcefully, according to Mendelson. But this did not happen when the participants took ecstasy, he pointed out.
``What this means is that the heart is working harder but with less efficiency,'' Mendelson explained. ``This probably decreases the amount of 'cardiac reserve,' meaning that additional demands on cardiac function may not be met.''
, 百拇医药
He noted that these changes may not have much of an effect on healthy young people, but in older people or those with undiagnosed heart disease, the effect could be ``quite serious.''
In the report, Mendelson and his colleagues note that the testing conditions of the study varied a great deal from how ecstasy is usually taken. They point out that many users take the drug while dancing in hot, crowded nightclubs, and they may take more than one dose or drink or take other drugs at the same time.
, 百拇医药
In addition, the effects of the drug may be different in people with cardiovascular disease than in the people in the study, who were all healthy.
In his remarks to Reuters Health, Mendelson commented that physical activity like dancing may compensate for the lack of ecstasy's effect on the heart's efficiency.
SOURCE: Annals of Internal Medicine 2000;133:969-973., 百拇医药