This prospective study compared personalized surgical antibiotic prophylaxis kits (SAPKs) with freely prescribed antibiotics. SAPKs use significantly enhanced national guidelines on surgical antibiotic prophylaxis application (82% vs 41%, P < 0.001), and result in limited errors in terms of antibiotic choice (3% vs 28%, P < 0.001), timing of administration (12% vs 24%, P = 0.003) and prophylaxis duration (1.5% vs 22%, P < 0.001), thereby demonstrating their effectiveness.