Reported Reactions

Drugs

Product name as reported

Colistin: adverse event reports filed with FDA

1,170 reports list it as a suspect or interacting product, 2005–2026.

1,170
reports as suspect product
0% of all reports · about 55 a year
61
reports, 12 months to June 2026
92 in the 12 months before
97.5%
marked serious by the reporter
57.4% across all reports
39.1%
record death among outcomes, as reported
458 reports · not verified by FDA

1,170 adverse event reports received by FDA list the product name "Colistin" as reporters wrote it as a suspect or interacting product, from April 2005 to June 2026. A further 1,345 reports list it only as a concomitant medication, and those are not counted in the figures on this page.

In the 12 months to June 2026, 61 reports listed it, down 34% from 92 in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Over its reporting history that is about 55 reports a year and 0% of the 20,646,523 reports in the database. How many people take it is not in the data, so a count is not a rate of occurrence.

The MedDRA terms listed most often are drug ineffective (28.5%), condition aggravated (12.1%) and drug resistance (11.6%). A report can list several reactions, so shares add to more than 100%; 357 different terms appear across these reports. Drug ineffective is recorded in 28.5% of these reports, against 6.3% of all reports in the database.

97.5% of the reports are marked serious by the reporter; 39.1% record death among the outcomes and 47.9% record hospitalisation, as reported. 59.8% of the reports came from other health professionals, and the largest patient age group is 45 to 64 (29.5%). FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event."

Reports by month, five years

01427Jul 2021: 27Aug 2021: 6Sep 2021: 19Oct 2021: 9Nov 2021: 10Dec 2021: 42022Jan 2022: 10Feb 2022: 11Mar 2022: 4Apr 2022: 15May 2022: 18Jun 2022: 8Jul 2022: 6Aug 2022: 7Sep 2022: 14Oct 2022: 5Nov 2022: 5Dec 2022: 52023Jan 2023: 5Feb 2023: 3Mar 2023: 11Apr 2023: 5May 2023: 3Jun 2023: 5Jul 2023: 25Aug 2023: 12Sep 2023: 7Oct 2023: 8Nov 2023: 12Dec 2023: 82024Jan 2024: 10Feb 2024: 7Mar 2024: 3Apr 2024: 2May 2024: 6Jun 2024: 5Jul 2024: 6Aug 2024: 6Sep 2024: 8Oct 2024: 8Nov 2024: 10Dec 2024: 132025Jan 2025: 13Feb 2025: 6Mar 2025: 9Apr 2025: 6May 2025: 5Jun 2025: 2Jul 2025: 5Aug 2025: 1Sep 2025: 8Oct 2025: 7Nov 2025: 9Dec 2025: 42026Jan 2026: 2Feb 2026: 2Mar 2026: 3Apr 2026: 4May 2026: 4Jun 2026: 12

Reports by the month FDA received them. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases.

By year received

0851692005: 420052006: 32007: 12009: 520092010: 42011: 82012: 520122013: 162014: 212015: 4120152016: 382017: 842018: 10120182019: 1692020: 1402021: 13220212022: 1082023: 1042024: 8420242025: 752026: 27

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Colistin reports recording the termall reports in the database

  1. Drug ineffectivethe medicine did not work as expected28.5%333
  2. Condition aggravatedthe condition being treated got worse12.1%142
  3. Septic shockshock arising from infection8.9%104
  4. Off label useused for a purpose or in a way not on the label8.7%102
  5. Multiple organ dysfunction syndromeseveral organs failing8.6%101
  6. Acute kidney injurysudden loss of kidney function7.1%83
  7. Endophthalmitisinfection inside the eye5.9%69
  8. Eye paineye pain5.9%69
  9. Choroiditis5.8%68
  10. Intraocular pressure increasedraised pressure in the eye5.2%61
  11. Uveitis5.2%61
  12. Visual acuity reducedreduced sharpness of vision5.2%61
  13. Deaththe patient died; cause not stated by this term5.1%60
  14. Sepsisa severe body-wide response to infection5%59
  15. Klebsiella infection4.4%52
  16. Renal failurekidney failure4%47
  17. Candida infectionthrush, a yeast infection3.8%45
  18. Thrombocytopenialow platelets3.7%43
  19. Product use issuea problem in how the product was used3.2%37
  20. Neutropenialow neutrophils, a type of white blood cell3%35
  21. Respiratory failurethe lungs could not supply enough oxygen3%35
  22. Hypotensionlow blood pressure2.8%33
  23. Pyrexiafever2.6%31
  24. Drug interactionan interaction between medicines2.6%30
  25. Infectionan infection, type not specified2.2%26
  26. Treatment failurethe treatment did not work2.1%25

Top 30 of 357 MedDRA preferred terms recorded across these reports, with a plain-language gloss where one is available. One report can record several terms. The hollow bar is the share of all reports in the database; it describes the reports, not the patients. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Outcomes recorded

Death39.1%458
Life-threatening18.5%216
Hospitalisation (initial or prolonged)47.9%560
Disability1%12
Congenital anomaly0.4%5
Other serious62.9%736
Not serious2.5%29

Outcome flags as the reporter set them; a report can carry several, and "other serious" is FDA's own category for serious reports outside the named outcomes. Grey bar: all 20,646,523 reports. FDA has not verified any outcome and states that the reports "cannot be used to estimate the incidence of these events."

Patients and reporters

Patient age

Under 24.5%53
2 to 113.4%40
12 to 173%35
18 to 4425%292
45 to 6429.5%345
65 to 7411.5%135
75 and over8.8%103
Age not given14.3%167

Patient sex

Female32.7%383
Male56.6%662
Not given10.7%125

Who reported

Physician28.7%336
Pharmacist3.5%41
Other health professional59.8%700
Lawyer0%0
Consumer or non-health professional6.2%72
Not given1.8%21

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 13.2% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Pseudomonas infection17414.9%
Klebsiella infection695.9%
Antibiotic therapy665.6%
Acinetobacter infection585%
Pneumonia413.5%
Bacterial infection403.4%

The indication field is filled in by the reporter and is often blank; shares are of all 1,170 reports.

Drugs most often listed in the same reports

Drug (any role in the report)ReportsShare of Colistin reports
Meropenem60151.4%
Vancomycin30125.7%
Tigecycline28524.4%
Ceftazidime19116.3%
Linezolid18615.9%
Amikacin18115.5%
Ciprofloxacin17715.1%
Tobramycin13811.8%
Metronidazole13211.3%
Piperacillin and tazobactam12410.6%

Other products listed in reports where Colistin is a suspect product, whatever their own role. Co-listing means the two were recorded together; it says nothing about either product's part in the event. Only the 2,500 most-reported names are counted here.

In context

MeasureColistinAll reports
Reports as suspect product1,17020,646,523
Share of that pool—0%
Reports, latest 12 months611,332,454
Marked serious97.5%57.4%
Death recorded among outcomes, per 1,000 reports39191
Hospitalisation recorded, per 1,000 reports479213
Consumer-filed share6.2%45.8%
Top term, share of reportsDrug ineffective 28.5%6.3%

Shares are of reports, not of patients treated. The number of people taking a product is not in the data, so none of these figures is a rate, and differences between columns reflect who takes a product, who reports and how long it has been sold. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Questions about Colistin reports

How many adverse event reports has FDA received for Colistin?

1,170 reports list Colistin as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 61 of them arrived in the latest 12 months. Another 1,345 list it only as a concomitant medication.

What reactions are recorded in Colistin reports?

drug ineffective (28.5%), condition aggravated (12.1%), drug resistance (11.6%), septic shock (8.9%) and off label use (8.7%). These are MedDRA preferred terms coded from what the reporter described; a report can list several, and a term's presence is not a finding that Colistin was responsible.

How serious are the reports?

97.5% are marked serious by the reporter. Among the outcomes recorded, 39.1% of reports include death and 47.9% include hospitalisation. FDA has not verified these outcomes and states that the reports "cannot be used to estimate the incidence" of the events.

Who files these reports?

other health professional (59.8%), physician (28.7%) and consumer or non-health professional (6.2%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Colistin rising?

61 reports in the 12 months to June 2026, down 34% from 92 in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Counts also move with how many people take a product, its time on the market and publicity.

Do these reports show that Colistin was responsible for these reactions?

No. FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event." The reaction may relate to the condition being treated, to other medicines, or to something else.

Is this a list of the side effects of Colistin?

No. It is a count of what was reported to FDA. The adverse reactions observed in clinical studies are printed on the FDA-approved label, which a pharmacist or clinician can go through with you.

How do I report an adverse event?

Consumers and health professionals can report to FDA through MedWatch (Form FDA 3500 online, or 1-800-FDA-1088), or to the manufacturer, which must pass reports on. See the guide on how to report.

Where this comes from. Counts are built from the openFDA Drug Adverse Event (FAERS) bulk export released 28 Sep 2026, which holds reports FDA received through 30 Jun 2026. Drug names are as reported, resolved to the brand or generic name on the FDA label where openFDA's harmonisation matched them; classes are the pharmacologic class (EPC) from the label and the National Drug Code Directory of 17 Sep 2026. A report counts here when it lists Colistin as a suspect or interacting product; reports listing it only as a concomitant medication (1,345) are excluded. No report narrative, lot number, patient detail or reporter identity is published. See the methodology and sources; FDA's record is authoritative, and corrections are handled within five working days.

Drug data (FAERS) through 30 Jun 2026; device data (MAUDE) through 31 Aug 2026. Not medical advice.