Reported Reactions

Drugs

Product name as reported

Ethambutol: adverse event reports filed with FDA

6,909 reports list it as a suspect or interacting product, 2004–2026. Also reported as Ethambutol Unspecified, Ethambutol /00022302/.

6,909
reports as suspect product
0% of all reports · about 309 a year
581
reports, 12 months to June 2026
655 in the 12 months before
91.6%
marked serious by the reporter
57.4% across all reports
14.5%
record death among outcomes, as reported
1,001 reports · not verified by FDA

6,909 adverse event reports received by FDA list the product name "Ethambutol" as reporters wrote it as a suspect or interacting product, from March 2004 to June 2026. A further 4,590 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, 581 reports listed it, down 11% from 655 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 309 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.

Reporters most often recorded drug ineffective (11.5%), drug reaction with eosinophilia and systemic symptoms (7.9%) and drug-induced liver injury (7.5%). A report can list several reactions, so shares add to more than 100%; 1,025 different terms appear across these reports. Drug ineffective is recorded in 11.5% of these reports, against 6.3% of all reports in the database.

91.6% of the reports are marked serious by the reporter; 14.5% record death among the outcomes and 35.3% record hospitalisation, as reported. 58.4% of the reports came from other health professionals, and the largest patient age group is 18 to 44 (28.1%). 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

054107Jul 2021: 37Aug 2021: 29Sep 2021: 43Oct 2021: 37Nov 2021: 58Dec 2021: 342022Jan 2022: 28Feb 2022: 29Mar 2022: 53Apr 2022: 54May 2022: 36Jun 2022: 47Jul 2022: 18Aug 2022: 45Sep 2022: 27Oct 2022: 55Nov 2022: 42Dec 2022: 512023Jan 2023: 37Feb 2023: 41Mar 2023: 14Apr 2023: 17May 2023: 36Jun 2023: 68Jul 2023: 45Aug 2023: 64Sep 2023: 37Oct 2023: 71Nov 2023: 62Dec 2023: 572024Jan 2024: 49Feb 2024: 55Mar 2024: 60Apr 2024: 46May 2024: 61Jun 2024: 52Jul 2024: 54Aug 2024: 40Sep 2024: 52Oct 2024: 49Nov 2024: 67Dec 2024: 1072025Jan 2025: 71Feb 2025: 64Mar 2025: 31Apr 2025: 44May 2025: 49Jun 2025: 27Jul 2025: 48Aug 2025: 43Sep 2025: 43Oct 2025: 36Nov 2025: 59Dec 2025: 672026Jan 2026: 91Feb 2026: 42Mar 2026: 50Apr 2026: 43May 2026: 32Jun 2026: 27

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

03496982004: 1020042005: 172006: 212007: 820072008: 32009: 222010: 1920102011: 142012: 612013: 21920132014: 2502015: 4322016: 43120162017: 5392018: 6982019: 64520192020: 4432021: 4832022: 48520222023: 5492024: 6922025: 58220252026: 285

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Ethambutol reports recording the termall reports in the database

  1. Drug ineffectivethe medicine did not work as expected11.5%795
  2. Drug reaction with eosinophilia and systemic symptomsDRESS, a severe reaction with rash, fever and organ involvement7.9%548
  3. Pyrexiafever5.9%406
  4. Paradoxical drug reaction5.9%405
  5. Condition aggravatedthe condition being treated got worse5.1%351
  6. Off label useused for a purpose or in a way not on the label5%348
  7. Drug interactionan interaction between medicines4.8%335
  8. Nauseafeeling sick3.9%270
  9. Mycobacterium avium complex infection3.6%248
  10. Vomitingbeing sick3.4%236
  11. Hepatotoxicityliver injury3.2%222
  12. Immune reconstitution inflammatory syndrome2.9%203
  13. Tuberculosistuberculosis2.9%199
  14. Drug intolerancethe medicine was not tolerated2.7%187
  15. Jaundiceyellowing of the skin or eyes2.6%182
  16. Dyspnoeashortness of breath2.5%175
  17. Treatment failurethe treatment did not work2.4%167
  18. Neuropathy peripheralnerve damage in hands or feet2.4%166
  19. Product use in unapproved indicationused for a purpose not on the label2.4%166
  20. Thrombocytopenialow platelets2.4%163
  21. Rashskin rash2.3%160
  22. Coughcough2.3%158
  23. Anaemialow red blood cells2.2%149
  24. Diarrhoealoose or frequent stools2.1%143
  25. Disease progressionthe disease advanced2.1%142
  26. Acute kidney injurysudden loss of kidney function2%141
  27. Weight decreasedweight loss2%135

Top 30 of 1,025 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

Death14.5%1,001
Life-threatening5.7%393
Hospitalisation (initial or prolonged)35.3%2,439
Disability1.8%122
Congenital anomaly0.4%26
Other serious70.4%4,866
Not serious8.4%582

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 21.2%83
2 to 112.6%177
12 to 173.2%224
18 to 4428.1%1,940
45 to 6420.1%1,388
65 to 7412.8%882
75 and over9.5%654
Age not given22.6%1,561

Patient sex

Female41.1%2,843
Male46.3%3,196
Not given12.6%870

Who reported

Physician33.8%2,333
Pharmacist2.3%160
Other health professional58.4%4,037
Lawyer0%0
Consumer or non-health professional4.1%280
Not given1.4%99

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 29.1% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Tuberculosis2,02229.3%
Pulmonary tuberculosis92813.4%
Mycobacterium avium complex infection88312.8%
Disseminated tuberculosis3374.9%
Mycobacterial infection2403.5%
Meningitis tuberculous1402%

The indication field is filled in by the reporter and is often blank; shares are of all 6,909 reports.

Drugs most often listed in the same reports

Drug (any role in the report)ReportsShare of Ethambutol reports
Isoniazid3,82455.3%
Pyrazinamide3,53751.2%
Rifampin2,83741.1%
Rifampicin1,94028.1%
Azithromycin1,22117.7%
Levofloxacin98914.3%
Amikacin91113.2%
Moxifloxacin88012.7%
Clarithromycin77511.2%
Linezolid76911.1%

Other products listed in reports where Ethambutol 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

MeasureEthambutolAll reports
Reports as suspect product6,90920,646,523
Share of that pool—0%
Reports, latest 12 months5811,332,454
Marked serious91.6%57.4%
Death recorded among outcomes, per 1,000 reports14591
Hospitalisation recorded, per 1,000 reports353213
Consumer-filed share4.1%45.8%
Top term, share of reportsDrug ineffective 11.5%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 Ethambutol reports

How many adverse event reports has FDA received for Ethambutol?

6,909 reports list Ethambutol as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 581 of them arrived in the latest 12 months. Another 4,590 list it only as a concomitant medication.

What reactions are recorded in Ethambutol reports?

drug ineffective (11.5%), drug reaction with eosinophilia and systemic symptoms (7.9%), drug-induced liver injury (7.5%), drug resistance (6%) and pyrexia (5.9%). 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 Ethambutol was responsible.

How serious are the reports?

91.6% are marked serious by the reporter. Among the outcomes recorded, 14.5% of reports include death and 35.3% 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 (58.4%), physician (33.8%) and consumer or non-health professional (4.1%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Ethambutol rising?

581 reports in the 12 months to June 2026, down 11% from 655 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 Ethambutol 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 Ethambutol?

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 Ethambutol as a suspect or interacting product; reports listing it only as a concomitant medication (4,590) 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.