Colistin Side Effects: What Studies Report

Regulatory status and how this page is framed

Colistin is a prescription medicine. For systemic infections it is administered as colistimethate sodium, an inactive prodrug that converts in the body to the active compound colistin, and it belongs to the polymyxin class of antibacterials described in reviews of aminoglycosides and polymyxins (PMID 19303668). It is an approved antibacterial medicine available by prescription in many jurisdictions and is used under the supervision of a treating clinician, who decides whether and how it is given.

This page summarises adverse events as they appear in published studies and in the descriptive literature, grouped by body system, with the study type and population noted where those details were reported. It does not duplicate the background page on the compound; that material sits at the colistin overview. This page is for educational purposes only and is not medical advice; consult a licensed physician about any medicine, symptom or treatment decision.

How adverse events for colistin have been studied

The evidence base cited here mixes study designs, and the design shapes what can be said about frequency. A multicentre, randomised, active-controlled, phase 3 non-inferiority trial compared sulbactam-durlobactam with colistin in patients with serious infections caused by the Acinetobacter baumannii-calcoaceticus complex, with patients in both groups receiving background carbapenem therapy, and that trial reported comparative rates of nephrotoxicity as a prespecified safety outcome (PMID 37182534). Case reports describe single patients and establish that an event can occur, not how often it occurs (PMID 25199193). Narrative reviews of preclinical data describe mechanisms and candidate protective strategies studied in laboratory animals rather than outcomes in treated patients (PMID 38091077).

Adverse events by system at a glance

Kidney Effects: What Studies Report

Kidney injury is the most consistently documented adverse event in the colistin literature cited here. In the randomised phase 3 trial comparing sulbactam-durlobactam with colistin in patients with serious Acinetobacter baumannii-calcoaceticus complex infections, researchers reported that nephrotoxicity occurred significantly less often in the sulbactam-durlobactam group than in the colistin group, while twenty-eight day all-cause mortality met the prespecified non-inferiority criterion (PMID 37182534). That comparison is reported here as trial data; it is not a ranking of one medicine against another for any individual, and the choice of agent in a given infection is made by the prescriber.

Beyond that trial, reviews of the class describe nephrotoxicity as the principal constraint on polymyxin use. A review of aminoglycosides and polymyxins characterised renal toxicity and neurological toxicity as the defining adverse effects of these older agents (PMID 19303668). A 2022 review of next-generation polymyxins described nephrotoxicity as a dose-limiting toxicity that has motivated the search for analogues with a wider therapeutic window (PMID 36551367). A chapter on the discovery of novel polymyxin-like antibiotics made the same point, framing reduced renal toxicity as a central design objective for new compounds in the class (PMID 31364086).

What the cited literature does not supply is a single pooled incidence figure across patient populations, or a breakdown by age, baseline kidney function or duration of therapy. The randomised trial provides comparative rates within its own enrolled population (PMID 37182534); the reviews describe the phenomenon qualitatively (PMID 36551367).

Nervous System Effects: What Studies Report

Neurological adverse events appear in the colistin literature mainly through case reports and preclinical work. A 2014 case report in BMJ Case Reports described colistin-mediated neurotoxicity in a treated patient, documenting that neurological manifestations were attributed to colistin therapy in that individual (PMID 25199193). A single case report establishes that the event has been observed and investigated, and does not establish how commonly it occurs.

A 2024 narrative review in Naunyn-Schmiedeberg's Archives of Pharmacology collected preclinical data on the prevention of colistin-induced neurotoxicity, summarising mechanistic pathways studied in laboratory models and the candidate protective agents that researchers had tested in those models (PMID 38091077). Because that review covered animal and laboratory studies, its findings describe experimental systems rather than outcomes measured in treated patients (PMID 38091077). The older class review likewise grouped neurological toxicity with renal toxicity as a recognised feature of polymyxins (PMID 19303668).

Electrolyte and Metabolic Effects: What Studies Report

A 2023 case report in Cureus described a Bartter-like syndrome in an adult receiving intravenous colistin, a renal tubular picture characterised by salt and potassium wasting with metabolic alkalosis, which the authors identified as a rare presentation associated with the medicine (PMID 38229782). The report sits at the rare end of the documented spectrum, and no frequency can be derived from a single published case (PMID 38229782). Electrolyte disturbance of this kind overlaps conceptually with the renal tubular effects discussed in class reviews of polymyxins (PMID 19303668).

Other Body Systems: What Studies Report

For several body systems, the verified citation set used on this page contains no structured adverse-event data, and that absence is stated plainly rather than filled in. There are no inhalation-route tolerability datasets, no dermatological or injection-site event tables, no gastrointestinal event rates and no hepatic laboratory outcome data among the papers cited here. The randomised phase 3 trial reported safety outcomes within its own protocol and population (PMID 37182534), while the remaining sources are reviews, chemistry papers and single case reports that were not designed to enumerate adverse events across organ systems (PMID 36551367). Approved product labelling is the reference document that collects reported adverse reactions for a specific marketed presentation, and a prescribing clinician or pharmacist can point to the labelling that applies to a given product.

Research aimed at reducing polymyxin toxicity

A substantial portion of the recent polymyxin literature is chemistry and formulation work motivated by the toxicity profile of the existing agents. Researchers synthesised polymyxins bearing reductively labile disulfide-linked lipids and evaluated the resulting analogues for antibacterial activity and toxicity characteristics in laboratory assays, an approach intended to separate antibacterial potency from unwanted effects (PMID 36399613). A discovery-focused chapter reviewed novel polymyxin-like antibiotics developed with the explicit aim of improving the therapeutic window of the class (PMID 31364086). A 2022 review described this next-generation polymyxin pipeline as a response to the toxicity and resistance pressures facing the older agents (PMID 36551367).

Formulation research has taken a parallel path. A 2023 study prepared technetium-99m labelled, colistin encapsulated theranostic liposomes and evaluated them in the context of Pseudomonas aeruginosa infection, combining imaging and delivery objectives in a preclinical system (PMID 36899198). None of these compounds or formulations is presented here as an available treatment option; they are described as laboratory and preclinical research programmes (PMID 36899198).

Measuring exposure: why toxicity research is technically difficult

Relating adverse events to drug exposure requires reliable measurement of both colistimethate sodium and colistin in biological samples. A 2019 chapter on the bioanalysis and stability of polymyxins described the analytical challenges involved, including the conversion and stability behaviour that complicates quantification in pharmacokinetic studies (PMID 31364072). Those measurement difficulties are one reason exposure-response relationships for toxicity have been hard to define precisely across the published literature (PMID 31364072).

A separate strand of research concerns bacterial resistance rather than patient tolerability. A 2022 update reviewed mobile colistin resistance determinants in non-fermentative gram-negative bacilli, describing how transferable resistance mechanisms have spread (PMID 35782127). Resistance is an epidemiological issue, not an adverse event, and it is mentioned here only to distinguish the two categories of finding (PMID 35782127).

What the cited evidence does not establish

• Overall incidence rates by system. Only the randomised phase 3 trial in the cited set reported comparative adverse-event frequencies, and those apply to its enrolled population (PMID 37182534).
• Risk factors for individuals. The case reports describe single patients and do not quantify who is more or less likely to experience an event (PMID 25199193, PMID 38229782).
• Prevention strategies in people. The 2024 narrative review covered preclinical data on preventing neurotoxicity, not interventions validated in treated patients (PMID 38091077).
• Reversibility and long-term outcomes. The cited papers do not provide follow-up datasets on recovery of kidney or nerve function after therapy ends (PMID 19303668).

Who decides about colistin

Whether colistin is appropriate in a given infection, how it is administered, what monitoring accompanies it and what happens if an adverse event appears are all decisions made by the prescribing clinician in light of the patient's circumstances, culture results and approved labelling. Nothing on this page is a recommendation to begin, continue, change or discontinue any medicine. Questions about symptoms experienced during treatment belong with the treating clinician or pharmacist, not with a summary of published literature.

Related reading

• Colistin: background overview
• Colistin benefits in the published literature
• Colistin compared with polymyxin B in studies
• How colistin works
• What colistin is used for

References

• Efficacy and safety of sulbactam-durlobactam versus colistin for the treatment of patients with serious infections caused by Acinetobacter baumannii-calcoaceticus complex: a multicentre, randomised, active-controlled, phase 3, non-inferiority clinical trial (ATTACK) (The Lancet Infectious Diseases, 2023)
• Colistin-mediated neurotoxicity (BMJ Case Reports, 2014)
• Prevention of colistin-induced neurotoxicity: a narrative review of preclinical data (Naunyn-Schmiedeberg's Archives of Pharmacology, 2024)
• IV Colistin: A Rare Cause of Bartter-Like Syndrome in Adults (Cureus, 2023)
• [Aminoglycosides and polymyxins] (Enfermedades Infecciosas y Microbiologia Clinica, 2009)
• Next-Generation Polymyxin Class of Antibiotics: A Ray of Hope Illuminating a Dark Road (Antibiotics, 2022)
• Discovery of Novel Polymyxin-Like Antibiotics (Advances in Experimental Medicine and Biology, 2019)
• Synthesis and Evaluation of Polymyxins Bearing Reductively Labile Disulfide-Linked Lipids (Journal of Medicinal Chemistry, 2022)
• (99m)Tc-Labeled, Colistin Encapsulated, Theranostic Liposomes for Pseudomonas aeruginosa Infection (AAPS PharmSciTech, 2023)
• Bioanalysis and Stability of Polymyxins (Advances in Experimental Medicine and Biology, 2019)
• An Update of Mobile Colistin Resistance in Non-Fermentative Gram-Negative Bacilli (Frontiers in Cellular and Infection Microbiology, 2022)