New medical guidelines are urging caution in taking antibiotics for bacterial sinus infections, countering a long-practiced treatment recommendation.

The new guidelines — issued by the American Academy of Otolaryngology-Head and Neck Surgery Foundation — are based on research that shows people who take antibiotics for sinusitis fare only slightly better than waiting for the infection to go away on its own, the Washington Post reports.

For years, the foundation recommended “watchful waiting” for people with sinusitis before they resort to antibiotics. The latest guidelines strengthen that recommendation, said Richard Rosenfeld, M.D., who chaired the group that devised the recommendations.

Antibiotics and watchful waiting are “both equally valid and recommended strategies for managing acute bacterial sinusitis,” said Dr. Rosenfeld, chairman of otolaryngology at SUNY Downstate Medical Center in Brooklyn.

“Even if you’re really sick and have a high fever, it’s still OK to initially observe without antibiotics because all the data from more than a dozen trials don’t really show that there’s any greater benefit.”

The guidelines suggest that patients with acute sinusitis wait 17 days, to see if the infection goes away on its own, before starting antibiotics. Those with chronic sinusitis, which can last 12 weeks or more, need to see a doctor to confirm a diagnosis and discuss treatment.

Dr. Rosenfeld said an analysis of studies found that 86 percent of patients taking a placebo for acute bacterial sinusitis got better in one to two weeks compared with 91 percent of those taking antibiotics.

The difference in outcomes is “statistically significant, but it really makes you question whether all these people need antibiotics,” he told the Journal.