Oct. 23 (HealthDay News) -- A three-day course of antibiotics may be as effective as a seven-day course in reducing pain after children have their tonsils removed, a new study has found.

The study appears in the October issue of the Archives of Otolaryngology -- Head & Neck Surgery.

Pain after a tonsillectomy can make children reluctant to eat and drink, leading to a risk of dehydration, noted Dr. Paul E. Johnson, of New York-Presbyterian Hospital/Weill Cornell Medical Center, and colleagues in a news release.

"The use of postoperative antibiotics to relieve pain following pediatric tonsillectomy was first reported more than 50 years ago," the study authors wrote. "It is thought that the normal oral bacterial flora colonize the denuded tonsilar fossae [cavity] and release inflammatory mediators that cause pain. Antibiotic use after tonsillectomy may quantitatively lessen the bacterial content and thus reduce pain."

The study included 49 children who underwent tonsillectomy with or without adenoidectomy (removal of glands in the back of the throat). After the surgery, 26 patients received antibiotics for seven days and 23 received three days of antibiotics followed by four days of a placebo.

The two groups had no statistically significant difference in pain or the amount of time it took the children to resume their normal diet and activities.

"Based on our results, a three-day course of antibiotics is as effective as a seven-day course," the researchers concluded. "A shorter course of antibiotics carries other potential advantages, including decreased cost, increased patient compliance with medications and a decrease in antibiotic-associated complications and bacterial resistance."

SOURCE: JAMA/Archives journals, news release, Oct. 19, 2009