What is colistin used for?
Colistin is an antibiotic used to treat infections caused by certain drug-resistant bacteria. It is most often used when other antibiotics are not effective or cannot be used, especially for severe infections from multidrug-resistant Gram-negative organisms like Pseudomonas aeruginosa and Acinetobacter baumannii.[1]
How does colistin work?
Colistin is a “polymyxin” antibiotic. It works by disrupting the bacterial cell membrane, which can kill susceptible bacteria.[1]
Is colistin the same as “colistin sulfate” or colistimethate?
In clinical practice, you may see related names:
- Colistin (often used to refer to the active drug)
- Colistin sulfate (a form used in some settings)
- Colistimethate sodium (a prodrug that is converted in the body to colistin)
The exact formulation matters because dosing and how the drug is administered depend on which form is used.[1]
Why is colistin sometimes limited?
Colistin can cause serious kidney toxicity (nephrotoxicity) and can affect nerves (neurotoxicity) in some patients. Because of these risks, clinicians monitor kidney function and adjust dosing as needed.[1]
What forms is colistin available in?
Depending on the country and clinical situation, colistin may be given:
- By intravenous (systemic) administration
- As inhaled/respiratory formulations for certain lung infections in people with resistant bacteria
Availability and the exact product vary by region.[1]
What bacteria is colistin effective against?
Colistin is used against specific Gram-negative bacteria that are resistant to many other antibiotics. The decision to use it typically depends on the lab’s susceptibility testing (the organism’s “minimum inhibitory concentration,” or MIC).[1]
Are there alternatives?
Alternatives depend on the organism and local resistance patterns. In many cases, other last-resort options may be considered first or alongside colistin, and newer agents may reduce the need for it in some settings.[1]
Sources
[1] https://en.wikipedia.org/wiki/Colistin