TUESDAY, Feb. 14 (HealthDay News) -- Treating a sinus infection with antibiotics doesn't speed recovery, new research shows.

"We did a randomized clinical trial among adults with a clinical diagnosis of acute sinusitis, and found no benefit from the antibiotic compared to the placebo for the treatment of acute sinusitis," said study author Dr. Jane Garbutt, a research associate professor of medicine and pediatrics at Washington University School of Medicine in St. Louis.

Still, one in five antibiotic prescriptions for adults in the United States are written for sinus infections, according to the study.

"Acute sinusitis is a miserable disease. People want something to make them feel better, and there are not very many treatment options, so patients ask their doctors for antibiotics. But, we think most of the time, acute sinusitis is a viral infection, so antibiotics won't help," said Garbutt.

Results of the study are published in the Feb. 15 issue of the Journal of the American Medical Association.

Sinusitis is an inflammation of the sinus cavities. Pain in the forehead is a common symptom, according to the National Institute of Allergy and Infectious Diseases (NIAID). Another common symptom of sinusitis is nasal secretions, which may drip down the back of the throat, according to NIAID. Colds and allergies are common causes of sinusitis, though sometimes bacteria are at fault.

Current guidelines from the U.S. Centers for Disease Control and Prevention recommend antibiotics only for those with moderately severe or severe symptoms.

Given the increase of bacteria resistance to antibiotics, the researchers wanted to test their effectiveness, so they looked at 166 adults diagnosed with acute sinusitis. Thirty-six percent of the study volunteers were male and 78 percent were white, according to the study. People with chronic sinusitis (lasting more than 28 days) weren't included, as they may need a different treatment, the authors noted.

Study participants were randomly assigned to receive 10 days' treatment with either 1,500 milligrams of amoxicillin (an antibiotic) spread out over three doses daily or a placebo. All of the volunteers were also given treatments for pain, fever, cough and nasal congestion, and told to use them as needed.

Symptoms and other measures of quality of life were measured in phone interviews at three, seven, 10 and 28 days after starting treatment.

At day three, there was no difference in the symptoms between groups. At day seven, there was a small improvement in the antibiotic group, but Garbutt said the change was likely too small for a patient to even notice a difference in symptoms. At 10 days, there was again no difference in symptoms between the two groups.

By day 10, about 80 percent of those in both groups reported that their symptoms were much improved or cured. At day 28, there was no difference in relapse rates, the researchers said.

Garbutt said there were no statistically significant differences between the groups for other measures, such as the need for medications to relieve symptoms or days of missed work.

"Most people will get better from acute sinusitis on their own, but many people feel if they're not getting an antibiotic, nothing is being done," said Dr. Richard Lebowitz, an otolaryngologist at New York University Langone Medical Center in New York City.

He said there are things people can do on their own that may help them feel better faster. Saline irrigation of the sinuses can help, he said, as can decongestant or mucous-thinning medications that are sold over-the-counter.

"The average viral upper respiratory infection lasts one to two weeks, and treatment of symptoms is probably the appropriate treatment up to that point," he said. But, if your infection lasts longer than a week or two, or your symptoms suddenly get significantly worse, you should see your doctor.

"Some people do have bacterial infections, and they can be hard to identify," said Garbutt, who also recommended following up with your doctor if your symptoms don't improve or they suddenly get worse.

More information

Learn more about sinusitis from the U.S. National Institute of Allergy and Infectious Diseases.