What does colistin mean?
Colistin is a powerful antibiotic, chemically known as polymyxin E, first isolated in the late 1940s from the soil bacterium Bacillus polymyxa subsp. colistinus. It belongs to the polymyxin family of drugs, which work by disrupting the outer membrane of certain bacteria. Although effective against many Gram-negative organisms, colistin fell out of favour for decades because it can cause kidney damage and neurological side effects. Its fortunes reversed dramatically in the twenty-first century: as bacteria grew resistant to modern front-line antibiotics, colistin was revived as a drug of last resort against dangerous pathogens such as Acinetobacter baumannii, Pseudomonas aeruginosa, and resistant strains of Klebsiella. Today it appears mainly in hospital settings, given intravenously or inhaled for severe respiratory infections, under careful monitoring. The emergence of bacteria resistant even to colistin has made it a focal point in global discussions about antimicrobial resistance, lending the word a distinctly grave clinical weight.
nounAn antibiotic drug, also known as polymyxin E, derived from the bacterium Bacillus polymyxa subsp. colistinus and used as a last-resort treatment for serious infections caused by multidrug-resistant Gram-negative bacteria.
- The antibiotic polymyxin E, produced by Bacillus polymyxa subsp. colistinus, used chiefly against multidrug-resistant Gram-negative bacteria such as Acinetobacter, Pseudomonas, and Klebsiella species.
"With carbapenem-resistant Klebsiella spreading through the ward, the physicians turned to colistin as a treatment of last resort."
"The microbiology report confirmed that the isolate was susceptible only to colistin."
"Because colistin can cause kidney damage and neurotoxicity, dosing must be carefully monitored."
Rarely pluralized in practice; the word normally functions as a mass noun referring to the drug substance. A plural may occasionally appear when distinguishing different formulations or salts.
"Different colistins, such as colistin sulfate and colistimethate sodium, are used for different routes of administration."
Discovered in 1949 and largely shelved because it damaged the kidneys, this old antibiotic was pulled off the shelf decades later when superbugs outsmarted nearly everything else we had.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of colistin
The name colistin derives from the bacterium Bacillus colistinus, from which the drug was first isolated around 1950; that organism's name in turn reflects its association with the intestinal flora of the colon, ultimately from Greek kolon. The word therefore entered English directly from scientific Latin nomenclature rather than through everyday speech. It shares its ultimate root with medical terms such as colitis, colonic, and colostomy, all referring to the large intestine.
How colistin is actually used
A technical medical term used almost exclusively in clinical and pharmacological contexts. It carries connotations of desperation or last-line therapy, since it is typically reserved for infections resistant to safer antibiotics.
Easily confused with colistin
Colostomy is a surgical opening of the colon onto the abdominal wall, whereas colistin is an antibiotic drug used to treat bacterial infections.