"Antibiotics appear to have no benefit in the treatment of acute upper respiratory tract infections," conclude Dr. Bruce Arroll and Dr. Timothy Kenealy of the University of Auckland, New Zealand. "The implications for practice are that prescription of antibiotics should not be given in the first instance as they will not improve the symptoms and adult patients will get adverse effects."
In addition to the side effects, mainly diarrhea, "overuse can increase levels of antibiotic resistance in the community," the review advises.
Colds are caused by viruses and not bacteria, upon which antibiotics act, yet, says Arroll, "There is evidence of high usage of antibiotics for the common cold in spite of doubts about the efficacy of such therapy." The review appears in the current issue of The Cochrane Library, a publication of The Cochrane Collaboration, an international organization that evaluates medical research. Systematic reviews draw evidence-based conclusions about medical practice after considering both the content and quality of existing medical trials on a topic. Arroll reviewed 12 trials that included more than 1,900 patients with symptoms lasting for seven days or less or with colds that included runny noses with colored discharge for 10 days or less. The patients had been given either antibiotics or placebo. "People receiving antibiotics did no better in terms of lack of cure or persistence of symptoms than those on placebo," Arroll says.
The goal of the study, according to the authors, was to determine if antibiotics reduce general cold symptoms such as sneezing, inflammation of the nose and throat; if antibiotics have any effect on pus-like nasal discharge; and if antibiotics have significant side eff ects in people with colds.
Although there may be some benefit of using antibiotics to treat the runny nose with colored discharge (acute purulent rhinitis), "their routine use is not recommended," the review says.
Colds are the most common reason for new patient visits at general practioners' offices, the review reports, and although the antibiotics do not work for that purpose, it is the second most common reason doctors prescribe them, Arroll writes.
"Physicians prescribe antibiotics in these cases out of habit and/or because they do not agree with the evidence," says Dr. Arroll. "Antibiotics do work for a minority of patients with purulent rhinitis, one out of five, so they may generalize this experience to their wider patient group."
Dr. Norman H. Edelman, chief medical officer for the American Lung Association, says, "There is no simple answer as to why providers do this. Some physicians may want to prevent complications of bacterial infections, which do occur. Some may be yielding to pressure from patients." But he says "this practice is on the decline as the public becomes more sophisticated about health issues."
Dr. Arroll says that patients are not doing themselves any favors looking for a "quick fix" in pressuring their providers to prescribe antibiotics for colds. "Patients will get a quicker fix if they take decongestants such as pseudoephedrine (Sudafed)," he says.