Drug · FAERS side-effect profile with label screen
Isoflurane side effects: what 1,935 FDA adverse event reports show
Who reports
1,935 reports · 94% serious · 299 with death outcome · 52% female
openFDA FAERS counts, all years, deduplication not applied
Used for
Isoflurane, USP liquid for inhalation may be used for induction and maintenance of general anesthesia. Adequate data have not been developed to establish its application in obstetrical anesthesia. Isoflurane, USP liquid for inhalation, a general anesthetic, is an inhalation agent indicated for induction and maintenance of general anesthesia. (1)
FDA label, Indications and Usage
What it is
11. DESCRIPTION Isoflurane, USP liquid for inhalation, a nonflammable liquid administered by vaporizing, is a general inhalation anesthetic drug. It is 1-chloro-2,2,2-trifluoroethyl difluoromethyl ether, and its structural formula is: Some physical constants are:
FDA label, Description section
Boxed warning
None in the current label
How to read this page. FAERS is a spontaneous-reporting system: counts are not incidence rates and a signal is not proof of causation.
Each reaction below is run through an automated screen — is the term in the FDA label (known), in the indications (the disease being treated), an administrative/coding term, or none of these (unlabeled)?
That screen is mechanical text matching, not a causality assessment. The 30 hand-written Bradford Hill assessments are on the causality assessment page. Not medical advice.
Causality screen of the 40 strongest signals
Labeled adverse reaction 13Labeled (related wording) 3Reporting / coding artifact 3Lab value / disease marker 1Not in label — unassessed 20
What the badges mean
- Labeled adverse reaction The exact term appears in the label's warnings or adverse-reactions sections: a known, expected effect. The FAERS signal confirms the label rather than discovering anything.
- Labeled (related wording) The label describes this effect under different wording (e.g. 'neutropenia' for 'neutrophil count decreased'). Treated as known.
- Reporting / coding artifact An administrative, monitoring or exposure term (product issue, off-label use, 'test normal', overdose...). Not a biological reaction; a high PRR here reflects how reports are coded.
- Lab value / disease marker A laboratory result, investigation or disease-activity marker (antibody positive, CRP abnormal, swollen joint count) not described in the label. These usually mirror the monitored disease or testing protocol rather than a drug effect; not screened further.
- Not in label — unassessed Not found in the label text, not an artifact pattern. This is a genuine candidate for a formal causality assessment (Bradford Hill / WHO-UMC); it has NOT had one here.
Strongest disproportionality signals
Flagged terms (PRR ≥ 2, χ² ≥ 4, n ≥ 10), ranked by PRR; infinite PRRs (no comparator reports) excluded. The EBGM column is a second, shrinkage-based estimate (MGPS) with its 5th percentile EB05 and the BCPNN IC025; a pair flagged by PRR alone is marked PRR-only and should be read as fragile. The strata column recomputes the PRR on serious reports only and flags pairs whose reports are unusually skewed by sex or come mostly from consumers rather than clinicians. 75 further terms are in the interactive explorer. Reaction links open the term's cross-drug page.
Show:
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Status epilepticus | 82 | 79.1 63.9–97.8ROR 82.5 · χ² 6,202 / p <1e-300 | 77.2 EB05 64.1 · IC025 +5.4 3/3 methods agree | Not in label — unassessed | serious PRR 48.2 · ♀ 95% (drug 52%) | no trial data cached |
| Multi-organ failure | 87 | 54.0 44.0–66.3ROR 56.5 · χ² 4,454 / p <1e-300 | 53.1 EB05 44.4 · IC025 +5.0 3/3 methods agree | Not in label — unassessed | serious PRR 33.0 | no trial data cached |
| Fear | 111 | 44.6 37.2–53.4ROR 47.2 · χ² 4,670 / p <1e-300 | 44.1 EB05 37.6 · IC025 +4.9 3/3 methods agree | Not in label — unassessed | serious PRR 37.0 | no trial data cached |
| Anhedonia | 94 | 38.6 31.7–47.0ROR 40.5 · χ² 3,397 / p <1e-300 | 38.2 EB05 32.1 · IC025 +4.7 3/3 methods agree | Not in label — unassessed | serious PRR 26.1 | no trial data cached |
| Renal injury | 100 | 36.2 29.9–43.8ROR 38.1 · χ² 3,383 / p <1e-300 | 35.9 EB05 30.3 · IC025 +4.6 3/3 methods agree | Labeled (related wording) related wording | serious PRR 22.2 | no trial data cached |
| Metabolic acidosis | 87 | 29.9 24.3–36.7ROR 31.2 · χ² 2,395 / p <1e-300 | 29.6 EB05 24.7 · IC025 +4.3 3/3 methods agree | Not in label — unassessed | serious PRR 18.1 · 92% clinician | no trial data cached |
| Cardiomegaly | 34 | 29.8 21.3–41.6ROR 30.3 · χ² 915 / p 3e-201 | 29.3 EB05 21.9 · IC025 +3.8 3/3 methods agree | Not in label — unassessed | serious PRR 18.7 · ♀ 91% (drug 52%) | no trial data cached |
| Ventricular fibrillation | 29 | 28.3 19.7–40.6ROR 28.7 · χ² 735 / p 4e-162 | 27.8 EB05 20.3 · IC025 +3.7 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 16.1 · 91% clinician | no trial data cached |
| Sinus tachycardia | 36 | 27.6 20.0–38.2ROR 28.1 · χ² 895 / p 8e-197 | 27.2 EB05 20.5 · IC025 +3.8 3/3 methods agree | Not in label — unassessed | serious PRR 17.2 · 100% clinician | no trial data cached |
| Intestinal perforation | 26 | 25.1 17.1–36.8ROR 25.5 · χ² 577 / p 7e-128 | 24.7 EB05 17.7 · IC025 +3.5 3/3 methods agree | Not in label — unassessed | serious PRR 15.4 · ♀ 100% (drug 52%) | no trial data cached |
| Drug exposure during pregnancy | 75 | 23.6 18.9–29.5ROR 24.5 · χ² 1,600 / p <1e-300 | 23.4 EB05 19.3 · IC025 +4.0 3/3 methods agree | Reporting / coding artifact | serious PRR 15.4 · ♀ 76% (drug 52%) · 98% clinician | no trial data cached |
| Caesarean section | 25 | 23.1 15.6–34.1ROR 23.4 · χ² 505 / p 3e-112 | 22.7 EB05 16.1 · IC025 +3.3 3/3 methods agree | Not in label — unassessed | serious PRR 12.8 | no trial data cached |
| Blood creatine phosphokinase increased | 62 | 23.0 18.0–29.4ROR 23.7 · χ² 1,283 / p 3e-281 | 22.8 EB05 18.4 · IC025 +3.9 3/3 methods agree | Lab value / disease marker | serious PRR 15.5 | no trial data cached |
| Shock | 48 | 22.8 17.3–30.2ROR 23.4 · χ² 980 / p 2e-215 | 22.6 EB05 17.7 · IC025 +3.7 3/3 methods agree | Not in label — unassessed | serious PRR 14.1 · ♀ 76% (drug 52%) | no trial data cached |
| Bronchospasm (airway tightening) | 29 | 22.0 15.3–31.6ROR 22.3 · χ² 560 / p 5e-124 | 21.7 EB05 15.8 · IC025 +3.4 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 14.9 · 100% clinician | no trial data cached |
| Injury | 137 | 21.0 17.9–24.7ROR 22.6 · χ² 2,600 / p <1e-300 | 21.0 EB05 18.2 · IC025 +4.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 16.0 | no trial data cached |
| Post procedural complication | 37 | 20.9 15.2–28.7ROR 21.3 · χ² 680 / p 4e-150 | 20.6 EB05 15.6 · IC025 +3.5 3/3 methods agree | Reporting / coding artifact | serious PRR 12.0 · 95% clinician | no trial data cached |
| Hyperkalaemia (high potassium) | 66 | 20.5 16.2–26.0ROR 21.2 · χ² 1,206 / p 1e-264 | 20.4 EB05 16.6 · IC025 +3.8 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 12.5 · 93% clinician | no trial data cached |
| Ventricular tachycardia | 31 | 20.3 14.3–28.8ROR 20.6 · χ² 549 / p 9e-122 | 20.0 EB05 14.7 · IC025 +3.4 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 12.1 · 92% clinician | no trial data cached |
| Muscle rigidity | 21 | 19.1 12.5–29.2ROR 19.3 · χ² 341 / p 2e-76 | 18.7 EB05 12.7 · IC025 +3.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 13.1 | no trial data cached |
| Ventricular extrasystoles | 18 | 18.8 11.9–29.8ROR 19.0 · χ² 285 / p 3e-64 | 18.3 EB05 12.0 · IC025 +2.9 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 12.8 | no trial data cached |
| Acute hepatic failure | 23 | 18.4 12.2–27.6ROR 18.6 · χ² 360 / p 1e-80 | 18.0 EB05 12.5 · IC025 +3.0 3/3 methods agree | Labeled (related wording) related wording | serious PRR 11.2 | no trial data cached |
| Sinus bradycardia | 16 | 17.9 11.0–29.2ROR 18.1 · χ² 239 / p 4e-54 | 17.3 EB05 10.9 · IC025 +2.7 3/3 methods agree | Not in label — unassessed | serious PRR 11.3 | no trial data cached |
| Unevaluable event | 124 | 17.8 15.0–21.1ROR 18.9 · χ² 1,952 / p <1e-300 | 17.7 EB05 15.2 · IC025 +3.8 3/3 methods agree | Reporting / coding artifact | serious PRR 19.3 | no trial data cached |
| Abscess | 25 | 17.0 11.5–25.1ROR 17.2 · χ² 361 / p 1e-80 | 16.7 EB05 11.7 · IC025 +3.0 3/3 methods agree | Not in label — unassessed | serious PRR 11.6 · ♀ 100% (drug 52%) | no trial data cached |
| Bradycardia (slow heart rate) | 80 | 16.3 13.2–20.3ROR 17.0 · χ² 1,138 / p 1e-249 | 16.2 EB05 13.4 · IC025 +3.5 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 9.7 · 98% clinician | no trial data cached |
| Brain oedema | 19 | 16.3 10.4–25.6ROR 16.5 · χ² 258 / p 2e-58 | 15.8 EB05 10.3 · IC025 +2.8 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 10.1 | no trial data cached |
| Electrocardiogram qt prolonged | 53 | 16.0 12.3–20.8ROR 16.4 · χ² 729 / p 6e-161 | 15.8 EB05 12.5 · IC025 +3.4 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 9.8 · ♀ 90% (drug 52%) · 90% clinician | no trial data cached |
| Ileus | 18 | 15.9 10.0–25.1ROR 16.0 · χ² 236 / p 1e-53 | 15.3 EB05 9.7 · IC025 +2.7 3/3 methods agree | Not in label — unassessed | serious PRR 9.8 | no trial data cached |
| Dystonia | 28 | 15.6 10.8–22.6ROR 15.8 · χ² 368 / p 2e-82 | 15.3 EB05 10.9 · IC025 +3.0 3/3 methods agree | Not in label — unassessed | serious PRR 10.6 · ♀ 100% (drug 52%) | no trial data cached |
| Myoclonus | 15 | 13.6 8.2–22.6ROR 13.7 · χ² 163 / p 1e-37 | 12.6 EB05 7.4 · IC025 +2.4 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 8.8 | no trial data cached |
| Tachypnoea | 17 | 13.6 8.5–21.9ROR 13.7 · χ² 186 / p 1e-42 | 12.7 EB05 7.8 · IC025 +2.5 3/3 methods agree | Not in label — unassessed | serious PRR 8.6 | no trial data cached |
| Supraventricular tachycardia | 12 | 13.6 7.7–23.9ROR 13.7 · χ² 128 / p 6e-30 | 12.1 EB05 6.6 · IC025 +2.2 3/3 methods agree | Not in label — unassessed | serious PRR 8.8 | no trial data cached |
| Renal failure acute | 53 | 13.4 10.2–17.4ROR 13.7 · χ² 594 / p 2e-131 | 13.1 EB05 10.3 · IC025 +3.1 3/3 methods agree | Labeled (related wording) related wording | serious PRR 8.1 · ♀ 25% (drug 52%) | no trial data cached |
| Renal failure (kidney failure) | 159 | 12.9 11.1–15.0ROR 14.0 · χ² 1,742 / p <1e-300 | 12.8 EB05 11.2 · IC025 +3.4 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 7.9 | no trial data cached |
| Hypotension (low blood pressure) | 236 | 12.8 11.3–14.4ROR 14.4 · χ² 2,573 / p <1e-300 | 12.7 EB05 11.4 · IC025 +3.4 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 8.7 | no trial data cached |
| Coagulopathy | 19 | 12.4 7.9–19.4ROR 12.5 · χ² 188 / p 5e-43 | 11.5 EB05 7.3 · IC025 +2.5 3/3 methods agree | Not in label — unassessed | serious PRR 7.5 | no trial data cached |
| Renal impairment | 95 | 12.3 10.1–15.0ROR 12.9 · χ² 979 / p 3e-215 | 12.2 EB05 10.2 · IC025 +3.2 3/3 methods agree | Not in label — unassessed | serious PRR 7.8 | no trial data cached |
| Premature baby | 33 | 11.9 8.5–16.6ROR 12.0 · χ² 317 / p 3e-71 | 11.4 EB05 8.2 · IC025 +2.8 3/3 methods agree | Not in label — unassessed | serious PRR 7.4 · ♀ 27% (drug 52%) · 90% clinician | no trial data cached |
| Stress | 77 | 11.6 9.3–14.5ROR 12.1 · χ² 738 / p 8e-163 | 11.4 EB05 9.4 · IC025 +3.1 3/3 methods agree | Not in label — unassessed | serious PRR 11.8 | no trial data cached |
Trial evidence (ClinicalTrials.gov)
Trial cross-check not yet run for this drug (ClinicalTrials.gov pull covers the 800 most-reported drugs first).
Most frequently reported reactions
By raw co-report count, regardless of disproportionality. Common terms here are often the illness itself or generic outcomes.
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Hypotension (low blood pressure) | 236 | 12.8 11.3–14.4ROR 14.4 · χ² 2,573 / p <1e-300 | 12.7 EB05 11.4 · IC025 +3.4 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 8.7 | no trial data cached |
| Renal failure (kidney failure) | 159 | 12.9 11.1–15.0ROR 14.0 · χ² 1,742 / p <1e-300 | 12.8 EB05 11.2 · IC025 +3.4 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 7.9 | no trial data cached |
| Injury | 137 | 21.0 17.9–24.7ROR 22.6 · χ² 2,600 / p <1e-300 | 21.0 EB05 18.2 · IC025 +4.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 16.0 | no trial data cached |
| Unevaluable event | 124 | 17.8 15.0–21.1ROR 18.9 · χ² 1,952 / p <1e-300 | 17.7 EB05 15.2 · IC025 +3.8 3/3 methods agree | Reporting / coding artifact | serious PRR 19.3 | no trial data cached |
| Drug interaction | 122 | 8.3 7.0–9.9ROR 8.8 · χ² 786 / p 3e-173 | 8.2 EB05 7.0 · IC025 +2.7 3/3 methods agree | Reporting / coding artifact | serious PRR 5.7 · 95% clinician | no trial data cached |
| Fear | 111 | 44.6 37.2–53.4ROR 47.2 · χ² 4,670 / p <1e-300 | 44.1 EB05 37.6 · IC025 +4.9 3/3 methods agree | Not in label — unassessed | serious PRR 37.0 | no trial data cached |
| Emotional distress | 104 | 9.3 7.7–11.2ROR 9.8 · χ² 764 / p 2e-168 | 9.1 EB05 7.7 · IC025 +2.8 3/3 methods agree | Not in label — unassessed | serious PRR 6.4 | no trial data cached |
| Renal injury | 100 | 36.2 29.9–43.8ROR 38.1 · χ² 3,383 / p <1e-300 | 35.9 EB05 30.3 · IC025 +4.6 3/3 methods agree | Labeled (related wording) related wording | serious PRR 22.2 | no trial data cached |
| Renal impairment | 95 | 12.3 10.1–15.0ROR 12.9 · χ² 979 / p 3e-215 | 12.2 EB05 10.2 · IC025 +3.2 3/3 methods agree | Not in label — unassessed | serious PRR 7.8 | no trial data cached |
| Anhedonia | 94 | 38.6 31.7–47.0ROR 40.5 · χ² 3,397 / p <1e-300 | 38.2 EB05 32.1 · IC025 +4.7 3/3 methods agree | Not in label — unassessed | serious PRR 26.1 | no trial data cached |
| Metabolic acidosis | 87 | 29.9 24.3–36.7ROR 31.2 · χ² 2,395 / p <1e-300 | 29.6 EB05 24.7 · IC025 +4.3 3/3 methods agree | Not in label — unassessed | serious PRR 18.1 · 92% clinician | no trial data cached |
| Multi-organ failure | 87 | 54.0 44.0–66.3ROR 56.5 · χ² 4,454 / p <1e-300 | 53.1 EB05 44.4 · IC025 +5.0 3/3 methods agree | Not in label — unassessed | serious PRR 33.0 | no trial data cached |
| Cardiac arrest (heart stopping) | 85 | 11.1 9.0–13.7ROR 11.6 · χ² 776 / p 5e-171 | 10.9 EB05 9.1 · IC025 +3.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 6.5 · 100% clinician | no trial data cached |
| Status epilepticus | 82 | 79.1 63.9–97.8ROR 82.5 · χ² 6,202 / p <1e-300 | 77.2 EB05 64.1 · IC025 +5.4 3/3 methods agree | Not in label — unassessed | serious PRR 48.2 · ♀ 95% (drug 52%) | no trial data cached |
| Bradycardia (slow heart rate) | 80 | 16.3 13.2–20.3ROR 17.0 · χ² 1,138 / p 1e-249 | 16.2 EB05 13.4 · IC025 +3.5 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 9.7 · 98% clinician | no trial data cached |
Unlabeled candidate signals
These flagged terms were not found in the FDA label text and do not match an artifact pattern. They are the pairs that would merit a structured assessment (temporality, dose-response, biological plausibility, consistency across databases, trial or cohort evidence). The screen has not done that; string-matching misses label wording, and a strong PRR can still be stimulated reporting, co-medication, or the disease itself.
- Status epilepticus — n=82, PRR 79.1
- Multi-organ failure — n=87, PRR 54.0
- Fear — n=111, PRR 44.6
- Anhedonia — n=94, PRR 38.6
- Metabolic acidosis — n=87, PRR 29.9
- Cardiomegaly — n=34, PRR 29.8
- Sinus tachycardia — n=36, PRR 27.6
- Intestinal perforation — n=26, PRR 25.1
- Caesarean section — n=25, PRR 23.1
- Shock — n=48, PRR 22.8
Want to assess one of these properly? The runbook describes the Bradford Hill / trial-evidence workflow used on the assessment page, and handoff_top1000_signals.csv lists the strongest unassessed pairs across all drugs.
Common questions
What are the most reported side effects of Isoflurane?
In FDA FAERS, the most frequently co-reported reaction terms for Isoflurane are hypotension, renal failure, injury, fear, emotional distress, renal injury. These are report counts, not rates: FAERS has no denominator, reporting is voluntary and uneven, and a term can be reported because of the illness being treated rather than the drug.
Does Isoflurane have an FDA boxed warning?
No. The FDA label retrieved for Isoflurane has no boxed warning; see the label's Warnings and Precautions for the recognised risks.
Do FAERS signals prove that Isoflurane causes these side effects?
No. A disproportionality signal (PRR, ROR) means a reaction is reported more often with this drug than with others in the database. That can reflect a real effect, but also the disease being treated, stimulated reporting after news or litigation, co-medications, or how reports are coded. Causality needs temporality, dose-response, biological plausibility, consistency across data sources and, ideally, trial or cohort evidence. This page screens each term against the FDA label and ClinicalTrials.gov results; it does not establish causation.
Sources & methods
- FDA label via openFDA (set ID 662ceaf6-650b-4dea-bbee-652f46426024, effective 20260105; matched on
openfda.generic_name.exact:"ISOFLURANE") - Bayesian shrinkage measures computed offline over all 1,317,300 cached pairs: BCPNN information component (IC, with Norén closed-form IC025) and MGPS empirical-Bayes geometric mean (EBGM, EB05) with a two-component gamma prior fitted by maximum marginal likelihood (α₁=0.57, β₁=0.02, α₂=1.42, β₂=0.70, w=0.17); unstratified
- FAERS pair statistics from the OpenPV build of 2026-09-14 (openFDA
count=aggregation, fieldpatient.drug.openfda.generic_name.exact, 115 reaction terms, min 3 co-reports); PRR/ROR with 95% CI, chi-square with Yates correction - Serious-only and stratified counts (serious:1, patient.patientsex, primarysource.qualification) from openFDA count queries; serious-only PRR uses the drug serious report total and the term global serious total (N_serious=11,882,979); strata shown only when n ≥ 20
- Seriousness and sex counts from openFDA
count=serious,patient.patientsex,seriousnessdeath
Page generated 2026-10-08. Label and PubChem text are retrieved automatically and may lag the current label; always check the current prescribing information. OpenPV is a beta research tool of the Open Source Medicine Foundation.