Clindamycin under pressure: resistance in hospitalized patients with odontogenic infections and a penicillin allergy label - a multicenter retrospective study.

Odontogenic infections may progress to deep space infection with systemic complications and require prompt surgical drainage and, when indicated, systemic antibiotics. In patients with a documented penicillin allergy label, empiric therapy is often shifted toward clindamycin, although resistance is increasingly reported. This multicenter retrospective cohort study included 88 hospitalized patients with surgically treated odontogenic infections and a documented penicillin allergy label at two German tertiary oral and maxillofacial surgery centers (Center A, n = 59; Center B, n = 29). Empiric antibiotic therapy was predominantly clindamycin-based (90.9%). Microbiological diagnostics were performed in 58.0% of patients and infections were mostly polymicrobial. Antimicrobial susceptibility testing was available in 43.2%; among cases with clindamycin testing, resistance was 76.7%. Antibiotic regimen changes occurred in 25.0%, most frequently to ampicillin/sulbactam. Median length of stay was 5 days; ICU-level care was required in 5.7%, revision surgery in 15.9%, one intracranial complication and one in-hospital death occurred. These findings suggest a clinically relevant mismatch between label-driven empiric clindamycin use and observed susceptibility patterns. Early structured allergy assessment and delabeling strategies may strengthen antibiotic stewardship and support safe first-line β-lactam use.