Medical College of Wisconsin
CTSICores SearchResearch InformaticsREDCap

Clinical use of the polymyxins: the tale of the fox and the cat. Int J Antimicrob Agents 2018 May;51(5):700-706



Pubmed ID




Scopus ID

2-s2.0-85044530489   12 Citations


BACKGROUND: There is a need to identify practice patterns of polymyxin use, quantify gaps in knowledge, and recognize areas of persistent confusion.

METHODS: A structured electronic survey was distributed to physicians, pharmacists and microbiologists. Demographic information was obtained, along with data regarding availability, stewardship principles, therapeutic usage, dosing, microbiological testing, and knowledge, attitudes and beliefs regarding the polymyxins.

RESULTS: In total, there were 420 respondents with a median of 8 (interquartile range 4-15) years of experience in infectious diseases (52.5%) and critical care (35%). Of the respondents who reported that only one polymyxin was available for use, 17.1% used polymyxin B. Over half (52.5%) of the respondents utilized a loading dose very often/always, and 66.8% dosed both polymyxins in milligrams, with the most common doses of colistin and polymyxin B being 2.5 mg/kg twice daily (60.3%) and 1.5 mg/kg twice daily (65%), respectively, for patients with normal renal function. Polymyxins were most often used for respiratory infections (63%) in combination with a carbapenem (63.6%). Approximately 85% of respondents reported their knowledge level to be fair, good or very good, although 34.9% answered two of the three knowledge questions incorrectly. More than 70% of respondents agreed that confusion exists in all surveyed areas of polymyxin use. Almost all respondents (91.2%) agreed that a polymyxin guideline would be a helpful resource.

CONCLUSIONS: This survey revealed objective and subjective variability in the use and perception of the polymyxins, and identified several areas in which they were being used contrary to the available evidence. The information provided herein lays the framework to harmonize clinical practice, guide future research and shape consensus guidelines.

Author List

Wenzler E, Bunnell KL, Danziger LH


Kristen B. Bresnehan PharmD Assistant Professor in the School of Pharmacy Administration department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Attitude of Health Personnel
Health Surveys
United States