Antimicrobial · FDA Approved
Polymyxin B
FDA-approved
01 · Overview
Polymyxin B is a cyclic lipopeptide antibiotic consisting of a heptapeptide ring and a tripeptide side chain acylated with a fatty acid tail. It binds lipopolysaccharide in the outer membrane of Gram-negative bacteria, causing membrane permeabilization and cell death, with its cationic residues interacting electrostatically with anionic phosphate groups on lipid A.
FDA drug approval records list approved polymyxin B sulfate products, including a currently marketed injection and older topical combination products, several of which are discontinued. It is reserved for serious infections caused by multidrug-resistant Gram-negative pathogens when other options are unavailable.
02 · Research summary & key findings
The systemic polymyxins, polymyxin B and colistin, have a long history of dose-limiting toxicity; nephrotoxicity is related to polymyxin exposure, with both dose size and therapy duration associated with its frequency, while neurotoxicity and hypersensitivity reactions are less common (PMID 25266910). Interest in therapeutic drug monitoring has grown as a way to minimize toxicity (PMID 25266910). In a real-world cohort of patients with carbapenem-resistant Gram-negative bacteria, an area under the concentration-time curve threshold was derived that predicted both clinical response and polymyxin B-related nephrotoxicity, supporting individualized dosing (PMID 36258197).
03 · Regulatory status
Polymyxin B has received FDA approval and is available for clinical use under appropriate medical supervision. Consult a qualified healthcare provider for prescribing information.
Polymyxin B is an FDA-approved medicine prescribed for the conditions on its label. It is not part of our intake, so we do not propose protocols for it. If you think it may be relevant to you, talk to your own doctor. How to ask your doctor.
04 · Administration routes
- Intravenous
- Intrathecal
- Topical
References
- [1]Adverse reactions associated with systemic polymyxin therapy Pharmacotherapy, 2015. PMID 25266910
- [2]An area under the concentration-time curve threshold as a predictor of efficacy and nephrotoxicity for individualizing polymyxin B dosing in patients with carbapenem-resistant gram-negative bacteria Crit Care, 2022. PMID 36258197
Primary literature
- PubMed: "Polymyxin B"
Peer-reviewed literature indexed by the National Library of Medicine.
- ClinicalTrials.gov: "Polymyxin B"
Registered interventional and observational studies, including status and phase.
- PubChem: "Polymyxin B"
Chemical structure, molecular properties, and bioactivity data.
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