Acetaminophen(乙酰氨基酚), the Unawared Poisoning Despite more than a decade’s worth of research showing that taking too much of

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问题                         Acetaminophen(乙酰氨基酚), the Unawared Poisoning
    Despite more than a decade’s worth of research showing that taking too much of a popular pain reliever can ruin the liver, the number of severe, unintentional poisonings from the drug is on the rise, a new study reports. The drug, acetaminophen, is best known under the brand name Tylenol. But many consumers don’t realize that it is also found in widely varying doses in several hundred common cold remedies and combination pain relievers.
    The authors of the study, which is appearing in the December issue of Hepatology(肝病学), say the combination of acetaminophen can make it too easy for some patients to swallow much more than the maximum recommended dose carelessly.
    "It’s extremely frustrating to see people come into the hospital who felt fine several days ago, but now need a new liver," said Dr. Tim Davern, one of the authors and a doctor with the liver transplant program of the University of California at San Francisco. "Most of them had no idea that what they were taking could have that sort of effect." The numbers of poisonings, however, are still tiny in comparison with the millions of people who use overthe-counter and doctor prescription drugs with acetaminophen.
Cases of Acetaminophen Poisoning
    Dr. Davern and a team of colleagues from other centers led by Dr. Anne Larson at the University of Washington Medical Center in Seattle, tracked the 662 consecutive patients who showed up with acute liver failure at 23 transplant centers across the United States from 1998 to 2003.
    Acetaminophen poisoning was to blame in nearly half the patients, the scientists found. The proportion of cases linked to the drug rose to 51 percent in 2003 from 28 percent in 1998. Not all the poisonings were accidental. An estimated 44 percent were suicide attempts by people who swallowed fistfuls of pills. "It’s a horrible way to die," Dr. Davern said, adding that patients who survive sometimes suffer profound brain damage.
    But in at least another 48 percent of the cases studied, the liver failed after a smaller, unintentional attack by the drug over several days. "I see some young women who have been suffering flu like symptoms for the better part of a week, and not eating much." Dr. Davern said. "They start with Tylenol, and maybe odd an over-the-counter flu medicine on top of  that, and pretty soon they’ve been taking maybe six grams of acetaminophen a day for a number of days. In rare cases that can be enough to throw them into liver failure."
The Labeling Must Be Improved
    Each Extra Strength Tylenol tablet contains half a gram, or 500 milligrams, of acetaminophen. One dose of Tylenol Cold and Flu Severe contains 1,000 milligrams. The recommended maximum daily dose for adults is 4 grams, or 4,000 milligrams.
    "Part of the problem is that the labeling on many of these drugs is still far from satisfactory," said Dr. William Lee, a liver specialist at the University of Texas Southwestern Medical Center in Dallas, who for years has been lobbying the Food and Drug Administration to make manufacturers put "acetaminophen" in large letters on the front of any package that contains it, so that as they reach for the bottle, patients will be more likely to pause and keep track of exactly how much they are swallowing.
    Some companies have voluntarily added new warnings about acetaminophen’s risk to the liver, and they should be given credit for that, said Dr. Charles Ganley, director of the F.D.A’s Office of Nonprescription Products. "But labeling isn’t where I would like it to be." Dr. Ganley added.
    Dr. Lee said he was disturbed by a pattern: "that acetaminophen is always billed as the one to reach to for safety, probably even more so now, with other pain relievers pulled from the market."
Safe Use of Acetaminophen
    In fact, the drug, when given in precise, appropriate doses is safer for children and teenagers than aspirin, which can interact with a viral infection to bring on rare but serious damage to the brain, liver and other organs in a series of symptoms known as Reye’s syndrome. And among adults, low doses of acetaminophen are less likely than aspirin to eat away at the stomach, worsen bleeding or harm the kidneys.
    Even patients with chronic liver disease are justly advised to take acetaminophen for the occasional fever, or a back injury or other illness, if they keep the total daily dose under about two grams, Dr. Lee said.
    Experts agree that a vast majority of people can safely take the 4 gram daily maximum that labels recommend for adults—the equivalent of eight Extra Strength Tylenol spread across 24 hours—and some people swallow much more without harm. But by eight grams in a single day, a significant number of people whose livers have been stressed by a virus, medication, alcohol or other factors would run into serious trouble, Dr. Lee said. Without intervention, about half the people who swallowed a single dose of 12 to 15 grams could die.
    How much alcohol over what time period is problematic? Recent research suggests the answer isn’t simple. The package labels now warn anyone who drinks three or more drinks everyday to consult a doctor before taking acetaminophen, but Dr. Lee thinks that people who are serf-controlled during the week but binge(饮酒作乐) on weekends may be dangerous, too.
    "Everyone really needs to be more aware." The experts say, "Otherwise, the pain reliever might be a killer."

选项 A、Y
B、N
C、NG

答案A

解析 题干指出乙酰氨基酚,也就是人们熟知的泰诺,如果过量服用的话就会对身体产生毒害作用。这与文章的主旨大意完全吻合。
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