To provide prescriptions of a topical composition of depsipeptide antibiotic lotilibcin having enhanced efficacy and safety for the application in the treatment and prevention of bacterial infections.SOLUTION: Provided is a topical composition that dramatically enhance the antibacterial effect of depsipeptide antibiotic lotilibcin in infectious disease models by blending boric acid in a low concentration equivalent to an additive that has no medicinal effect, specifically 0.01 to 5.0 mass so as to improve safety by reducing dosage, administration period and frequency.SELECTED DRAWING: Figure 2【課題】デプシペプチド系抗生物質ロチリブシンの細菌感染症治療・予防用途に適用する有効性・安全性を高めた外用組成物の処方を提供する。【解決手段】医薬品効果をもたない添加剤相当の低濃度、具体的には０.０１～５.０質量のホウ酸を配合することにより、デプシペプチド系抗生物質ロチリブシンの感染症モデルにおける抗菌効果を飛躍的に高め、投与量、投与期間・頻度低減による安全性向上をもたらす外用処方組成物が提供される。【選択図】図２
