The findings offer another reason for doctors to limit  their use of the drugs, which are overused in the United  States, the team at the U.S. Centers for Disease Control and  Prevention said. “This number is an important reminder for physicians and  patients that antibiotics can have serious side effects and  should only be taken when necessary,” said the CDC’s Dr. Daniel  Budnitz, who led the study. For the first report ever done on adverse reactions to  antibiotics in the United States, the researchers used the  National Electronic Injury Surveillance System-Cooperative  Adverse Drug Event Surveillance project, a sample of 63 U.S.  hospitals, between 2004 and 2006. They found more than 6,600 emergency visits were due to an  adverse reaction to an antibiotic. They used formulas to  extrapolate this to the whole country and estimated that  142,000 such emergency visits are made every year. “Systemic antibiotics (pills or injections as opposed to  creams) were implicated in 19.3 percent of all emergency  department visits for drug-related adverse events,” they wrote  in the September 15 issue of Clinical Infectious Diseases. Penicillin and related antibiotics such as amoxicillin,  widely prescribed and widely seen as safe, accounted for half  the emergency visits. Other classes of antibiotics such as  cephalosporins, fluoroquinolones and newer antibiotics  accounted for the rest. “Persons aged 15-44 years accounted for an estimated 41.2  percent of ED visits. Infants accounted for only an estimated  6.3 percent of ED visits,” they wrote. Budnitz and colleagues said 78 percent of the adverse  events in the study were allergic reactions, ranging from rash  to a serious reaction known as anaphylaxis, and the remaining  22 percent were caused by errors and overdoses. Many studies have suggested that half of the estimated 100  million antibiotic prescriptions written for respiratory tract  infections in the United States are unnecessary. Most such  infections are caused by viruses, and antibiotics are useless  against them. But, Budnitz and colleagues said, doctors still often  believe their patients are exceptions to the rule and continue  to write the prescriptions. “Because antibiotics are frequently used, both  appropriately and inappropriately, if doctors would reduce the  number of antibiotics they prescribe to their patients by even  a small percentage, we could significantly reduce the number of  emergency visits for antibiotic adverse events,” Budnitz said  in a statement. “Antibiotics are among the most frequently used medications  in the United States. Annually, antibiotics are prescribed to  an estimated 16 percent of patients during ambulatory care  visits, and pharmaceutical manufacturers spend $1 billion  promoting antibiotics,” Budnitz wrote.
Study finds 140,000 bad reactions to antibiotics.