Fernández Rubio, BeatrizHerrera Hidalgo, LauraLuque Márquez, RafaelAlarcón, Arístides deLópez-Cortés, Luis E.Luque Pardos, SòniaGutiérrez Urbón, José MaríaFernández Polo, AntoniGil Navarro, María V.Gutiérrez Valencia, Alicia2024-04-242024-04-242023Fernández-Rubio B, Herrera-Hidalgo L, Luque-Márquez R, de Alarcón A, López-Cortés LE, Luque-Pardos S, et al. Stability of ampicillin plus ceftriaxone combined in elastomeric infusion devices for outpatient parenteral antimicrobial therapy. Antibiotics (Basel). 2023 Feb 22;12(3):432. DOI: 10.3390/antibiotics120304322079-6382http://hdl.handle.net/10230/59879Currently, ampicillin plus ceftriaxone (AC) is one of the preferred treatments for Enterococcus faecalis infective endocarditis. However, there is a lack of stability data for the combination of both drugs in elastomeric devices, so the inclusion of AC in Outpatient Parenteral Antimicrobial Therapy (OPAT) programs is challenging. The objective of the study was to determine the stability of AC in elastomeric pumps when stored at 8 ± 2 °C, 25 ± 2 °C, 30 ± 2 °C and 37 ± 2 °C using LC-MS/MS. The combination was diluted in 0.9% sodium chloride and the final concentrations were ampicillin 24 g/L plus ceftriaxone 8 g/L. Physical and chemical stability were evaluated at 12, 20, 24, 36 and 48 h after preparation. Stability was met at each time point if the percentage of intact drug was ≥90% of its respective baseline concentration and color and clearness remained unchanged. The drug combination was stable for 48 h when it was kept at 8 ± 2 °C. At 25 ± 2 °C and 30 ± 2 °C, they were stable for 24 h of storage. At 37 ± 2 °C, the stability criterion was not met at any time point. These results prove that AC could be included in OPAT programs using elastomeric infusion devices for the treatment of E. faecalis infections.application/pdfeng© 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).info:eu-repo/semantics/articlehttp://dx.doi.org/10.3390/antibiotics12030432StabilityOutpatient parenteral antimicrobial therapyElastomersAmpicillinCeftriaxoneInfective endocarditisinfo:eu-repo/semantics/openAccess