Grant: Project Grant

Cellulitis is a painful bacterial skin infection that is treated with antibiotics. It is the 9th most common reason for an emergency department (ED) visit in Canada. Oral antibiotics are preferred over intravenous antibiotics because of increased patient convenience, fewer complications and decreased cost. When selecting oral antibiotics, most Canadian ED clinicians prescribe standard-dose cephalexin (500 mg four times daily). However, 20% of ED cellulitis patients fail oral antibiotic therapy. When this happens, treatment is commonly escalated to intravenous antibiotics and patients often need hospitalization. High-dose cephalexin (1000 mg four times daily) may cause fewer treatment failures. There has never been a head-to-head comparison of high-dose versus standard-dose cephalexin. We are conducting a clinical trial to compare standard-dose to high-dose cephalexin to determine if high-dose cephalexin is superior and results in fewer treatment failures for ED adults with cellulitis. Our primary outcome is oral antibiotic treatment failure, which involves a change in antibiotic treatment (escalation to intravenous antibiotics or change in class of oral antibiotic) due to worsening infection within 7 days. Other outcomes include clinical cure, adverse events, unplanned hospitalization and unscheduled visits to see a doctor. We have successfully completed a pilot clinical trial to demonstrate that a larger, definitive trial is feasible. If high-dose cephalexin is found to be superior to standard-dose cephalexin, the results will improve cellulitis care in Canada and around the world with the potential to reduce unnecessary intravenous antibiotic use, hospitalization, and costs.