Mesna Injection side effects: what 8,213 FDA adverse event reports show
Drug class
Cytoprotective agent
Who reports
8,213 reports · 97% serious · 1,722 with death outcome · 47% female
Used for
1. INDICATIONS AND USAGE Mesna injection is indicated as a prophylactic agent in reducing the incidence of ifosfamide-induced hemorrhagic cystitis. Limitation of Use: Mesna injection is not indicated to reduce the risk of hematuria due to other pathological conditions such as thrombocytopenia.
What it is
11. DESCRIPTION Mesna injection is a detoxifying agent to inhibit the hemorrhagic cystitis induced by ifosfamide. The active ingredient, mesna, USP is a synthetic sulfhydryl compound designated as sodium-2- sulphanylethanesulphonate with a molecular formula of C 2 H 5 NaO 3 S 2 and a molecular weight of 164.2.
Boxed warning
None in the current label
Causality screen of the 40 strongest signals
What the badges mean
- Likely indication confounding The term appears in the label's indications: reports probably describe the disease being treated (or its progression), not a drug effect. Classic confounding by indication.
- 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. 958 further terms are in the interactive explorer. Reaction links open the term's cross-drug page.
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| T-cell lymphoma refractory | 11 | 1,154.0 565.5–2,355.1ROR 1,155.6 · χ² 7,917 / p <1e-300 | 332.9 EB05 198.4 · IC025 +3.5 3/3 methods agree | Not in label — unassessed | serious n=11 | no trial data cached |
| Lymphoid tissue hypoplasia | 40 | 941.3 655.0–1,352.7ROR 945.9 · χ² 26,667 / p <1e-300 | 515.5 EB05 394.8 · IC025 +5.7 3/3 methods agree | Not in label — unassessed | serious n=40 | no trial data cached |
| Thymus hypoplasia | 42 | 826.2 583.4–1,169.9ROR 830.4 · χ² 25,446 / p <1e-300 | 484.3 EB05 373.4 · IC025 +5.7 3/3 methods agree | Not in label — unassessed | serious n=42 | no trial data cached |
| Human bocavirus infection | 23 | 351.0 227.0–542.6ROR 352.0 · χ² 6,741 / p <1e-300 | 245.4 EB05 172.3 · IC025 +4.7 3/3 methods agree | Not in label — unassessed | serious n=23 | no trial data cached |
| Secondary immunodeficiency | 91 | 210.6 170.2–260.5ROR 212.9 · χ² 17,326 / p <1e-300 | 186.8 EB05 156.8 · IC025 +6.2 3/3 methods agree | Not in label — unassessed | serious n=91 | no trial data cached |
| Mycobacterium chelonae infection | 52 | 194.0 146.4–257.0ROR 195.2 · χ² 9,091 / p <1e-300 | 169.1 EB05 133.9 · IC025 +5.6 3/3 methods agree | Not in label — unassessed | serious n=52 | no trial data cached |
| Pseudomonal sepsis | 109 | 168.4 138.9–204.2ROR 170.6 · χ² 16,844 / p <1e-300 | 153.7 EB05 130.9 · IC025 +6.2 3/3 methods agree | Not in label — unassessed | serious n=109 | no trial data cached |
| Cystitis bacterial | 21 | 167.9 108.0–261.0ROR 168.3 · χ² 3,111 / p <1e-300 | 138.0 EB05 95.2 · IC025 +4.4 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=21 | no trial data cached |
| Norovirus test positive | 20 | 167.9 106.8–263.8ROR 168.3 · χ² 2,955 / p <1e-300 | 137.1 EB05 93.7 · IC025 +4.3 3/3 methods agree | Lab value / disease marker | serious n=20 | no trial data cached |
| Idiopathic pneumonia syndrome | 18 | 164.2 102.0–264.4ROR 164.6 · χ² 2,590 / p <1e-300 | 132.8 EB05 88.9 · IC025 +4.1 3/3 methods agree | Not in label — unassessed | serious n=18 | no trial data cached |
| Cystitis viral | 23 | 164.1 107.7–250.0ROR 164.5 · χ² 3,348 / p <1e-300 | 136.8 EB05 96.0 · IC025 +4.5 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=23 | no trial data cached |
| Sars-cov-2 test negative | 40 | 158.6 115.3–218.2ROR 159.4 · χ² 5,746 / p <1e-300 | 139.5 EB05 106.8 · IC025 +5.2 3/3 methods agree | Reporting / coding artifact | serious n=40 · ♀ 13% (drug 47%) · 98% clinician | no trial data cached |
| Anal inflammation | 37 | 157.9 113.4–220.0ROR 158.6 · χ² 5,282 / p <1e-300 | 138.2 EB05 104.7 · IC025 +5.1 3/3 methods agree | Not in label — unassessed | serious n=37 · ♀ 0% (drug 47%) · 97% clinician | no trial data cached |
| Disseminated aspergillosis | 25 | 143.7 96.1–214.9ROR 144.2 · χ² 3,218 / p <1e-300 | 123.4 EB05 87.9 · IC025 +4.6 3/3 methods agree | Not in label — unassessed | serious n=25 | no trial data cached |
| Cancer fatigue | 12 | 142.5 79.7–254.9ROR 142.7 · χ² 1,465 / p <1e-300 | 111.5 EB05 68.0 · IC025 +3.4 3/3 methods agree | Not in label — unassessed | serious n=12 | no trial data cached |
| Engraft failure | 13 | 121.7 69.8–212.2ROR 121.9 · χ² 1,371 / p 2e-300 | 99.6 EB05 61.9 · IC025 +3.5 3/3 methods agree | Not in label — unassessed | serious n=13 | no trial data cached |
| Red blood cell transfusion | 16 | 106.3 64.5–175.2ROR 106.5 · χ² 1,502 / p <1e-300 | 91.2 EB05 59.5 · IC025 +3.8 3/3 methods agree | Not in label — unassessed | serious n=16 | no trial data cached |
| Herpes zoster reactivation | 10 | 102.8 54.6–193.3ROR 102.9 · χ² 873 / p 4e-192 | 83.5 EB05 48.5 · IC025 +3.0 3/3 methods agree | Not in label — unassessed | serious n=10 | no trial data cached |
| Tumour compression | 12 | 100.0 56.2–178.1ROR 100.2 · χ² 1,038 / p 4e-228 | 83.8 EB05 51.1 · IC025 +3.3 3/3 methods agree | Not in label — unassessed | serious n=12 | no trial data cached |
| Cystitis haemorrhagic | 147 | 96.9 82.3–114.1ROR 98.6 · χ² 13,344 / p <1e-300 | 92.3 EB05 80.4 · IC025 +5.9 3/3 methods agree | Likely indication confounding term in indications | serious n=147 · 91% clinician | no trial data cached |
| Enterobacter bacteraemia | 11 | 96.5 52.9–176.2ROR 96.6 · χ² 911 / p 2e-200 | 80.4 EB05 47.9 · IC025 +3.2 3/3 methods agree | Not in label — unassessed | serious n=11 | no trial data cached |
| Acute polyneuropathy | 10 | 94.3 50.2–177.2ROR 94.4 · χ² 802 / p 9e-177 | 77.9 EB05 45.2 · IC025 +3.0 3/3 methods agree | Not in label — unassessed | serious n=10 | no trial data cached |
| Restrictive cardiomyopathy | 10 | 86.2 45.9–161.9ROR 86.3 · χ² 734 / p 6e-162 | 72.4 EB05 42.0 · IC025 +3.0 3/3 methods agree | Not in label — unassessed | serious n=10 | no trial data cached |
| Candida test positive | 12 | 75.2 42.3–133.4ROR 75.3 · χ² 782 / p 2e-172 | 65.7 EB05 40.1 · IC025 +3.3 3/3 methods agree | Lab value / disease marker | serious n=12 | no trial data cached |
| Fanconi syndrome | 40 | 74.8 54.6–102.3ROR 75.1 · χ² 2,756 / p <1e-300 | 70.3 EB05 53.8 · IC025 +4.7 3/3 methods agree | Not in label — unassessed | serious n=40 · 100% clinician | no trial data cached |
| Abscess bacterial | 10 | 73.4 39.2–137.6ROR 73.5 · χ² 625 / p 3e-138 | 63.2 EB05 36.7 · IC025 +3.0 3/3 methods agree | Not in label — unassessed | serious n=10 | no trial data cached |
| Platelet transfusion | 34 | 69.8 49.7–98.0ROR 70.1 · χ² 2,176 / p <1e-300 | 65.5 EB05 49.0 · IC025 +4.5 3/3 methods agree | Not in label — unassessed | serious n=34 · 94% clinician | no trial data cached |
| Mantle cell lymphoma recurrent | 11 | 67.2 37.0–122.3ROR 67.3 · χ² 636 / p 1e-140 | 59.1 EB05 35.2 · IC025 +3.1 3/3 methods agree | Not in label — unassessed | serious n=11 | no trial data cached |
| Venoocclusive disease | 61 | 63.7 49.4–82.0ROR 64.1 · χ² 3,609 / p <1e-300 | 61.0 EB05 49.2 · IC025 +4.9 3/3 methods agree | Not in label — unassessed | serious n=61 · ♀ 15% (drug 47%) · 91% clinician | no trial data cached |
| Metastases to the mediastinum | 10 | 62.9 33.6–117.9ROR 63.0 · χ² 536 / p 8e-119 | 55.3 EB05 32.1 · IC025 +2.9 3/3 methods agree | Not in label — unassessed | serious n=10 | no trial data cached |
| Engraftment syndrome | 14 | 62.3 36.7–105.8ROR 62.4 · χ² 765 / p 1e-168 | 56.4 EB05 35.7 · IC025 +3.4 3/3 methods agree | Not in label — unassessed | serious n=14 | no trial data cached |
| Parainfluenzae virus infection | 36 | 60.8 43.7–84.5ROR 61.0 · χ² 2,008 / p <1e-300 | 57.6 EB05 43.5 · IC025 +4.5 3/3 methods agree | Not in label — unassessed | serious n=36 | no trial data cached |
| Enterobacter infection | 36 | 55.9 40.2–77.7ROR 56.2 · χ² 1,846 / p <1e-300 | 53.3 EB05 40.2 · IC025 +4.4 3/3 methods agree | Not in label — unassessed | serious n=36 | no trial data cached |
| Aplastic anaemia | 110 | 54.7 45.3–66.0ROR 55.4 · χ² 5,623 / p <1e-300 | 53.1 EB05 45.3 · IC025 +5.1 3/3 methods agree | Not in label — unassessed | serious n=110 · 96% clinician | no trial data cached |
| Cerebral toxoplasmosis | 19 | 52.9 33.6–83.3ROR 53.0 · χ² 898 / p 1e-197 | 49.4 EB05 33.5 · IC025 +3.7 3/3 methods agree | Not in label — unassessed | serious n=19 | no trial data cached |
| Febrile neutropenia | 1,274 | 50.1 47.6–52.7ROR 59.1 · χ² 60,203 / p <1e-300 | 49.1 EB05 46.9 · IC025 +5.5 3/3 methods agree | Not in label — unassessed | serious PRR 29.0 · 96% clinician | no trial data cached |
| Fusarium infection | 13 | 49.4 28.6–85.6ROR 49.5 · χ² 559 / p 9e-124 | 45.5 EB05 28.3 · IC025 +3.2 3/3 methods agree | Not in label — unassessed | serious n=13 | no trial data cached |
| Scrotal pain | 10 | 48.1 25.8–90.0ROR 48.2 · χ² 408 / p 5e-91 | 43.6 EB05 25.3 · IC025 +2.8 3/3 methods agree | Not in label — unassessed | serious n=10 | no trial data cached |
| Cytomegalovirus viraemia | 79 | 46.9 37.6–58.5ROR 47.4 · χ² 3,441 / p <1e-300 | 45.6 EB05 37.8 · IC025 +4.8 3/3 methods agree | Not in label — unassessed | serious n=78 · ♀ 25% (drug 47%) | no trial data cached |
| Aplasia | 36 | 46.8 33.7–65.1ROR 47.0 · χ² 1,541 / p <1e-300 | 45.0 EB05 34.0 · IC025 +4.3 3/3 methods agree | Not in label — unassessed | serious n=36 | no trial data cached |
Trial evidence (ClinicalTrials.gov)
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 |
|---|---|---|---|---|---|---|
| Febrile neutropenia | 1,274 | 50.1 47.6–52.7ROR 59.1 · χ² 60,203 / p <1e-300 | 49.1 EB05 46.9 · IC025 +5.5 3/3 methods agree | Not in label — unassessed | serious PRR 29.0 · 96% clinician | no trial data cached |
| Pyrexia (fever) | 681 | 5.0 4.7–5.4ROR 5.4 · χ² 2,226 / p <1e-300 | 5.0 EB05 4.7 · IC025 +2.2 3/3 methods agree | Labeled (related wording) related wording | serious PRR 3.6 · 94% clinician | no trial data cached |
| Off label use (used outside approved label) | 647 | 1.9 1.8–2.0ROR 2.0 · χ² 288 / p 6e-65 | 1.9 EB05 1.8 · IC025 +0.8 | Reporting / coding artifact | serious PRR 2.0 · 96% clinician | no trial data cached |
| Neutropenia (low neutrophils (infection-fighting cells)) | 574 | 10.9 10.0–11.7ROR 11.6 · χ² 5,138 / p <1e-300 | 10.8 EB05 10.1 · IC025 +3.3 3/3 methods agree | Not in label — unassessed | serious PRR 6.6 · 95% clinician | no trial data cached |
| Thrombocytopenia (low platelets) | 397 | 9.1 8.3–10.0ROR 9.5 · χ² 2,866 / p <1e-300 | 9.0 EB05 8.3 · IC025 +3.0 3/3 methods agree | Likely indication confounding term in indications; also in warnings | serious PRR 5.5 · 94% clinician | no trial data cached |
| Anaemia (low red blood cells) | 391 | 5.2 4.8–5.8ROR 5.5 · χ² 1,346 / p 6e-295 | 5.2 EB05 4.8 · IC025 +2.2 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 3.4 · 94% clinician | no trial data cached |
| Vomiting | 378 | 2.1 1.9–2.3ROR 2.1 · χ² 209 / p 1e-47 | 2.1 EB05 1.9 · IC025 +0.9 | Labeled adverse reaction exact term | serious PRR 1.8 · 94% clinician | no trial data cached |
| Pancytopenia (all blood cells low) | 365 | 16.8 15.2–18.6ROR 17.6 · χ² 5,394 / p <1e-300 | 16.7 EB05 15.3 · IC025 +3.9 3/3 methods agree | Labeled (related wording) related wording | serious PRR 9.9 · 97% clinician | no trial data cached |
| Nausea | 363 | 1.2 1.1–1.3ROR 1.2 · χ² 10 / p 1e-3 | 1.2 EB05 1.1 · IC025 +0.1 | Labeled adverse reaction exact term | serious PRR 1.3 · 93% clinician | no trial data cached |
| Sepsis (blood infection) | 358 | 8.2 7.4–9.1ROR 8.5 · χ² 2,265 / p <1e-300 | 8.1 EB05 7.4 · IC025 +2.8 3/3 methods agree | Not in label — unassessed | serious PRR 4.9 · 92% clinician | no trial data cached |
| Mucosal inflammation | 342 | 33.9 30.6–37.7ROR 35.4 · χ² 10,766 / p <1e-300 | 33.4 EB05 30.6 · IC025 +4.8 3/3 methods agree | Labeled (related wording) related wording | serious PRR 20.7 · 95% clinician | no trial data cached |
| Diarrhoea (diarrhea) | 340 | 1.3 1.2–1.5ROR 1.4 · χ² 31 / p 1e-8 | 1.3 EB05 1.2 · IC025 +0.3 | Labeled adverse reaction exact term | serious PRR 1.4 · 92% clinician | no trial data cached |
| Pneumonia (lung infection) | 285 | 2.3 2.0–2.5ROR 2.3 · χ² 200 / p 1e-45 | 2.2 EB05 2.0 · IC025 +1.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 1.4 · 93% clinician | no trial data cached |
| Disease progression | 279 | 6.1 5.4–6.8ROR 6.2 · χ² 1,175 / p 8e-258 | 6.0 EB05 5.4 · IC025 +2.4 3/3 methods agree | Reporting / coding artifact | serious PRR 4.1 · 96% clinician | no trial data cached |
| Death | 252 | 0.7 0.7–0.8ROR 0.7 · χ² 22 / p 1e-6 | 0.7 EB05 0.7 · IC025 -0.6 PRR-only: not supported by EBGM or IC | Outcome field, not a reaction | serious PRR 0.4 · 90% 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.
- Lymphoid tissue hypoplasia — n=40, PRR 941.3
- Thymus hypoplasia — n=42, PRR 826.2
- Human bocavirus infection — n=23, PRR 351.0
- Secondary immunodeficiency — n=91, PRR 210.6
- Mycobacterium chelonae infection — n=52, PRR 194.0
- Pseudomonal sepsis — n=109, PRR 168.4
- Anal inflammation — n=37, PRR 157.9
- Disseminated aspergillosis — n=25, PRR 143.7
- Fanconi syndrome — n=40, PRR 74.8
- Platelet transfusion — n=34, PRR 69.8
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 Mesna?
In FDA FAERS, the most frequently co-reported reaction terms for Mesna are febrile neutropenia, pyrexia, neutropenia, thrombocytopenia, anaemia, vomiting. 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 Mesna have an FDA boxed warning?
No. The FDA label retrieved for Mesna has no boxed warning; see the label's Warnings and Precautions for the recognised risks.
Do FAERS signals prove that Mesna 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 49e9c804-9e88-4774-8faf-35bd61b3a8e9, effective 20260127; matched on
openfda.generic_name.exact:"MESNA") - 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, 998 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.