Twenty six adult patients with chronic sinusitis who had undergone Caldwell-Luc operation and received conservative therapy for a long time, but still complained of nasal symptoms, were treated with 400-600mg of erythromycin (EM) per day for 7.9 months on the average.
1) Rhinorrhea was reduced in 60.0%, postnasal drip in 50.0%, nasal obstruction in 60.0%, hyposmia in 11.8% and sense of dullness in the head in 100%.
2) Rhinoscopy showed reduced mucosal swelling in 10.5%, lower volume of rhinorrhea in 80.0%, better quality of rhinorrhea in 70.0% and reduced postnasal drip in 85.7%.
3) This therapy was effective even when EM-resistant bacteria such as Hemophilus influenzae were present.
4) No significant side effects were noted in any of the patients during this therapy. Long-term low-dose EM therapy is useful in the treatment of chronic sinusitis. We consider that its effect is not due to its antibacterial activity but to some as yet unknown mechanism.