It causes itchy eyes, facial pressure, a runny nose, and general feeling of lousiness. Unfortunately, according to new research published in the Journal of the American Medical Association, the antibiotics you're likely taking for sinus infections aren't doing anything to make you feel better.

Sinusitis is one of the most common infections in the United States. Its 24 million annual cases account for nearly one fifth of all antibiotic prescriptions. Because sinusitis can be caused by either a virus or bacteria, by definition, antibiotics won't have any effect on the viral infections. And, according to the AMA report, it doesn't have any effect on the bacterial infection either.

Amoxicillin, the most commonly prescribed antibiotic prescribed to treat sinus infections, doesn't work any better than a placebo, according to Jay Piccirillo of Washington University School of Medicine, one of the authors of the study.

After three days, patients who were prescribed amoxicillin didn't feel any better than those who received a placebo. Because sinusitis usually goes away on its own, it's better to not take any antibiotics at all, Piccirillo says.

But try telling that to someone with sinusitis.

"People say, 'Look doc, I took off from work, I paid an $89 copay, and you're telling me to take Tylenol,'" Piccirillo says. "It sounds cruel maybe, but by saying, 'I want antibiotics,' you've made the assumption they make you better quicker, but they don't."

Piccirillo says more doctors should be sending patients toward over-the-counter medicines that treat the symptoms and let a patient's body take care of the infection on its own. If the patient isn't feeling better after 10 days, that's another story—the vast majority of sinusitis infections are "acute," or short-lived, but anything lasting longer might require more treatment.

The researchers say doctors should have patients wait at least that long before prescribing antibiotics. Although amoxicillin is most often prescribed, Piccirillo says at least 29 different antibiotics, "most of which don't even have FDA indications for sinusitis," are prescribed for the infection.

By demanding antibiotics as soon as they experience symptoms, patients are wasting their money, he says, and can be helping breed antibiotic-resistant bacteria in their bodies.

Patients often take a few days' worth of amoxicillin and then "save it for the next [infection]," he says. By taking the antibiotic, patients aren't doing themselves any favors—remaining bacteria will have built up a resistance to that antibiotic. Although resistance in streptococcus bacteria, one of the main causes of sinusitis, hasn't been seen much yet, Piccirillo says there's no reason to encourage the bugs to develop it.