( Health.com ) -- Roughly 20 % of the antibiotic prescriptions written in the United States for adults each year are for sinus infections . That 's an impressive statistic , given that doctors and public health officials have long doubted that antibiotics can successfully treat the condition . A new study , published this week in the Journal of the American Medical Association , appears to confirm those doubts : The antibiotic amoxicillin was no better than placebo at improving the congestion , cough , runny nose , pain , and other symptoms that accompany sinus infections ( also known as acute sinusitis ) , researchers found . `` Compared to placebo , amoxicillin does n't seem to provide any benefits , '' says lead author Jane Garbutt , an associate professor at the Washington University School of Medicine , in St. Louis . `` In terms of patient satisfaction , side effects , symptom relief , days missed from work , et cetera , we did not see any difference . '' Health.com : Is it a cold ? Or a sinus infection ? Most sinus infections are caused by viruses , which do n't respond to antibiotics . But even bacterial sinus infections rarely require antibiotic treatment , according to the Centers for Disease Control and Prevention . In most cases , both types of infection go away on their own in less than two weeks . `` Most patients get better despite antibiotics , not because of them , '' says Garbutt . `` There is a high rate of spontaneous resolution . '' Antibiotics would be more useful if doctors were able to distinguish between viral and bacterial sinusitis . But general practitioners have no tests at their disposal that reliably diagnose bacterial infections , Garbutt says , and in the study she and her colleagues were unable to identify any symptoms or other markers that predicted which patients would respond to antibiotics . `` The problem for primary care physicians is figuring out which patients would benefit , '' she says . Health.com : How to tell if you need an antibiotic . The study included 166 people with moderate or severe sinus infections . Half of the participants took amoxicillin three times a day for 10 days , and the other half took a placebo on the same schedule . In addition , every patient was given acetaminophen , cough medicine , and decongestants to use as needed . The two groups of patients improved at approximately the same rate . By day three , just over one-third of those in each group reported a lessening of their symptoms , a proprotion that increased to roughly 80 % in each group by day 10 . The patients taking antibiotics did feel measurably better than the placebo group on day seven , but the researchers did not consider the difference to be clinically ( as opposed to statistically ) significant . On that day , the difference in the two groups ' quality of life -- as measured by a scale appropriately named SNOT-16 -- was negligible , the study notes . Health.com : 10 products that can ease sinus symptoms . The results reinforce what many doctors have suspected , even if they 've continued to prescribe antibiotics to sinusitis patients , says Daniel Merenstein , M.D. , an assistant professor of family medicine at Georgetown University Medical Center , in Washington , D.C. `` We do n't practice it , but we do know it , '' he says . `` This study might help us give out fewer antibiotics . '' The main reason doctors continue to prescribe antibiotics is that patients have come to expect them , Garbutt and her colleagues note . One way of satisfying patients without overusing antibiotics , Garbutt says , is to give them a prescription but advise them not to fill it unless their symptoms persist or worsen -- a protocol that 's become popular in Europe . Garbutt says it 's also vital that doctors talk to their patients about which treatments work , which do n't , and why . `` You have to have some communication plan , '' she says . `` You need to provide information about what they should expect and what to do if their condition deteriorates . '' Health.com : Surprising causes of sinus trouble . Patient expectations are n't the only driver of antibiotic use for sinus infections , however . Mark Shikowitz , M.D. , director of the Zucker Nasal and Sinus Center at North Shore -- Long Island Jewish Health System , in New Hyde Park , New York , says some doctors prescribe the drugs to guard against the very rare chance that a sinus infection will progress to something much worse , such as a brain abscess , a bundle of cells that can develop following a bacterial infection . `` The chances are quite small , but the outcome if it does happen can be catastrophic , '' Shikowitz says . `` And behind every bad outcome is a medical malpractice attorney . '' Some doctors will be reluctant to withhold or discourage antibiotics until physician organizations formally adopt the conservative approach advocated by Garbutt and her colleagues as the new standard of care , he says . The overuse of antibiotics for sinusitis has important public-health implications in light of the growing concerns about antibiotic-resistant bacteria and viruses . Widespread antibiotic use can lead the infectious organisms that cause disease to adapt a defense , making the drug less effective in the population overall . Copyright Health Magazine 2011 .
Doctors still prescribing antibiotics for sinus infections , despite evidence they do n't work . Comment: Even bacterial sinus infections rarely require antibiotic treatment , the CDC says .