Drug · FAERS side-effect profile with label screen
Cefazolin Sodium side effects: what 11,982 FDA adverse event reports show
Drug class
Cephalosporin antibacterial
FDA label, Indications wording
Who reports
11,982 reports · 93% serious · 1,387 with death outcome · 49% female
openFDA FAERS counts, all years, deduplication not applied
Used for
Cefazolin for Injection is a cephalosporin antibacterial indicated for: Treatment of the following infections caused by susceptible isolates of the designated microorganisms in adult and pediatric patients 1 month of age and older for whom appropriate .
FDA label, Indications and Usage
What it is
Cefazolin for Injection contains cefazolin sodium, a semi-synthetic cephalosporin. It is the sodium salt of 3-{[(5-methyl-1,3,4-thiadiazol-2-yl)thio]-methyl}-8-oxo-7-[2-(1H-tetrazol-1-yl) acetamido]-5-thia-1-azabicyclo [4.2.0]oct-2-ene-2-carboxylic acid.
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
Likely indication confounding 1Reporting / coding artifact 4Lab value / disease marker 3Not in label — unassessed 32
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. 1,061 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 |
|---|---|---|---|---|---|---|
| Lymphoid tissue hypoplasia | 83 | 2,238.4 1,616.4–3,099.7ROR 2,254.0 · χ² 79,843 / p <1e-300 | 795.0 EB05 661.5 · IC025 +6.8 3/3 methods agree | Not in label — unassessed | serious n=83 · ♀ 0% (drug 49%) | no trial data cached |
| Thymus hypoplasia | 81 | 1,570.8 1,163.2–2,121.4ROR 1,581.5 · χ² 65,709 / p <1e-300 | 688.1 EB05 571.3 · IC025 +6.7 3/3 methods agree | Not in label — unassessed | serious n=81 · ♀ 0% (drug 49%) | no trial data cached |
| Multiple lentigines syndrome | 13 | 897.5 459.3–1,753.9ROR 898.5 · χ² 7,080 / p <1e-300 | 316.0 EB05 196.5 · IC025 +3.8 3/3 methods agree | Not in label — unassessed | serious n=13 | no trial data cached |
| Hypoprothrombinaemia | 64 | 470.1 356.8–619.3ROR 472.6 · χ² 23,177 / p <1e-300 | 332.8 EB05 269.8 · IC025 +6.2 3/3 methods agree | Not in label — unassessed | serious n=64 · 100% clinician | no trial data cached |
| Mechanical ventilation complication | 27 | 385.1 253.9–584.3ROR 386.0 · χ² 8,146 / p <1e-300 | 257.7 EB05 186.0 · IC025 +4.9 3/3 methods agree | Reporting / coding artifact | serious n=27 · ♀ 0% (drug 49%) · 100% clinician | no trial data cached |
| Pericarditis fungal | 12 | 383.6 205.2–716.8ROR 383.9 · χ² 3,440 / p <1e-300 | 209.7 EB05 127.8 · IC025 +3.6 3/3 methods agree | Not in label — unassessed | serious n=12 | no trial data cached |
| Disseminated aspergillosis | 78 | 349.7 274.3–445.7ROR 352.0 · χ² 22,262 / p <1e-300 | 271.6 EB05 224.7 · IC025 +6.3 3/3 methods agree | Not in label — unassessed | serious n=78 · ♀ 0% (drug 49%) | no trial data cached |
| Mycobacterial peritonitis | 16 | 349.6 204.3–598.1ROR 350.0 · χ² 4,339 / p <1e-300 | 216.1 EB05 141.0 · IC025 +4.1 3/3 methods agree | Not in label — unassessed | serious n=16 | no trial data cached |
| Gastritis fungal | 12 | 227.6 124.7–415.4ROR 227.8 · χ² 2,196 / p <1e-300 | 152.8 EB05 93.2 · IC025 +3.5 3/3 methods agree | Not in label — unassessed | serious n=12 | no trial data cached |
| Allergy test negative | 17 | 214.2 129.4–354.4ROR 214.5 · χ² 3,022 / p <1e-300 | 157.3 EB05 104.0 · IC025 +4.1 3/3 methods agree | Reporting / coding artifact | serious n=17 | no trial data cached |
| Purpura senile | 13 | 213.7 120.1–380.1ROR 213.9 · χ² 2,263 / p <1e-300 | 149.1 EB05 92.7 · IC025 +3.6 3/3 methods agree | Not in label — unassessed | serious n=13 | no trial data cached |
| Vitamin k deficiency | 41 | 201.0 145.6–277.7ROR 201.7 · χ² 7,131 / p <1e-300 | 166.3 EB05 127.8 · IC025 +5.3 3/3 methods agree | Not in label — unassessed | serious n=41 · 100% clinician | no trial data cached |
| Mycobacterium fortuitum infection | 19 | 200.0 124.4–321.4ROR 200.3 · χ² 3,195 / p <1e-300 | 152.2 EB05 103.0 · IC025 +4.2 3/3 methods agree | Not in label — unassessed | serious n=19 | no trial data cached |
| Inspiratory capacity decreased | 27 | 190.2 127.9–282.9ROR 190.6 · χ² 4,408 / p <1e-300 | 153.1 EB05 110.5 · IC025 +4.7 3/3 methods agree | Not in label — unassessed | serious n=27 · ♀ 0% (drug 49%) · 100% clinician | no trial data cached |
| Burkholderia test positive | 11 | 169.5 91.3–314.8ROR 169.7 · χ² 1,528 / p <1e-300 | 122.3 EB05 72.9 · IC025 +3.3 3/3 methods agree | Lab value / disease marker | serious n=11 | no trial data cached |
| Recurrence of neuromuscular blockade | 14 | 153.9 89.1–265.8ROR 154.1 · χ² 1,815 / p <1e-300 | 118.9 EB05 75.3 · IC025 +3.7 3/3 methods agree | Not in label — unassessed | serious n=13 | no trial data cached |
| Postoperative delirium | 15 | 151.4 89.3–256.6ROR 151.6 · χ² 1,924 / p <1e-300 | 118.6 EB05 76.3 · IC025 +3.8 3/3 methods agree | Not in label — unassessed | serious n=15 | no trial data cached |
| Airway peak pressure increased | 12 | 150.1 83.2–270.6ROR 150.2 · χ² 1,501 / p <1e-300 | 113.7 EB05 69.3 · IC025 +3.4 3/3 methods agree | Lab value / disease marker | serious n=12 | no trial data cached |
| Confusion postoperative | 10 | 143.8 75.5–274.1ROR 144.0 · χ² 1,181 / p 5e-259 | 106.5 EB05 61.8 · IC025 +3.1 3/3 methods agree | Not in label — unassessed | serious n=10 | no trial data cached |
| Arthrodesis | 70 | 129.4 101.5–164.8ROR 130.1 · χ² 8,175 / p <1e-300 | 116.6 EB05 95.5 · IC025 +5.6 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=70 · ♀ 100% (drug 49%) | no trial data cached |
| Chorioamnionitis | 13 | 126.8 72.2–222.6ROR 126.9 · χ² 1,396 / p <1e-300 | 101.1 EB05 62.8 · IC025 +3.5 3/3 methods agree | Not in label — unassessed | serious n=13 | no trial data cached |
| Vancomycin infusion reaction | 22 | 112.7 73.2–173.4ROR 112.9 · χ² 2,182 / p <1e-300 | 97.1 EB05 67.6 · IC025 +4.3 3/3 methods agree | Not in label — unassessed | serious n=22 | no trial data cached |
| Tarsal tunnel syndrome | 13 | 109.5 62.5–191.7ROR 109.6 · χ² 1,214 / p 3e-266 | 89.8 EB05 55.8 · IC025 +3.5 3/3 methods agree | Not in label — unassessed | serious n=13 | no trial data cached |
| Incision site infection | 44 | 87.9 65.0–118.9ROR 88.2 · χ² 3,515 / p <1e-300 | 80.8 EB05 62.7 · IC025 +4.9 3/3 methods agree | Not in label — unassessed | serious n=44 · ♀ 100% (drug 49%) · 100% clinician | no trial data cached |
| Meningitis fungal | 10 | 78.5 41.6–147.8ROR 78.5 · χ² 659 / p 1e-145 | 66.1 EB05 38.3 · IC025 +3.0 3/3 methods agree | Not in label — unassessed | serious n=10 | no trial data cached |
| Clostridium test positive | 89 | 74.4 60.2–91.9ROR 75.0 · χ² 6,111 / p <1e-300 | 70.4 EB05 58.9 · IC025 +5.3 3/3 methods agree | Lab value / disease marker | serious n=89 · 100% clinician | no trial data cached |
| Maternal exposure during delivery | 35 | 65.4 46.7–91.6ROR 65.6 · χ² 2,076 / p <1e-300 | 61.0 EB05 45.9 · IC025 +4.5 3/3 methods agree | Reporting / coding artifact | serious n=33 · ♀ 100% (drug 49%) | no trial data cached |
| Procedural hypotension | 30 | 63.5 44.1–91.3ROR 63.6 · χ² 1,719 / p <1e-300 | 59.1 EB05 43.4 · IC025 +4.3 3/3 methods agree | Not in label — unassessed | serious n=30 · 100% clinician | no trial data cached |
| Kounis syndrome | 77 | 61.7 49.2–77.4ROR 62.1 · χ² 4,381 / p <1e-300 | 58.8 EB05 48.6 · IC025 +5.1 3/3 methods agree | Not in label — unassessed | serious n=77 · ♀ 28% (drug 49%) · 100% clinician | no trial data cached |
| Foetal exposure during delivery | 23 | 60.8 40.1–92.1ROR 60.9 · χ² 1,249 / p 5e-274 | 56.2 EB05 39.4 · IC025 +4.0 3/3 methods agree | Reporting / coding artifact | serious n=23 | no trial data cached |
| Tryptase increased | 22 | 56.4 36.9–86.2ROR 56.5 · χ² 1,107 / p 6e-243 | 52.3 EB05 36.4 · IC025 +3.9 3/3 methods agree | Not in label — unassessed | serious n=22 | no trial data cached |
| Pyroglutamic acidosis | 11 | 52.2 28.6–95.0ROR 52.2 · χ² 487 / p 3e-108 | 46.8 EB05 27.9 · IC025 +3.0 3/3 methods agree | Not in label — unassessed | serious n=11 | no trial data cached |
| Hyperthermia malignant | 39 | 47.4 34.5–65.2ROR 47.6 · χ² 1,681 / p <1e-300 | 45.2 EB05 34.5 · IC025 +4.3 3/3 methods agree | Not in label — unassessed | serious n=38 · 94% clinician | no trial data cached |
| Cataract subcapsular | 16 | 47.2 28.7–77.5ROR 47.3 · χ² 660 / p 7e-146 | 43.8 EB05 28.6 · IC025 +3.4 3/3 methods agree | Not in label — unassessed | serious n=16 | no trial data cached |
| Allergic oedema | 17 | 46.9 29.0–76.0ROR 47.0 · χ² 700 / p 1e-154 | 43.7 EB05 28.9 · IC025 +3.5 3/3 methods agree | Not in label — unassessed | serious n=17 | no trial data cached |
| Diabetic retinal oedema | 12 | 42.2 23.8–74.8ROR 42.2 · χ² 432 / p 4e-96 | 38.9 EB05 23.7 · IC025 +3.0 3/3 methods agree | Not in label — unassessed | serious n=12 | no trial data cached |
| Anaphylactic shock | 601 | 42.0 38.8–45.5ROR 44.2 · χ² 23,479 / p <1e-300 | 41.0 EB05 38.3 · IC025 +5.2 3/3 methods agree | Not in label — unassessed | serious PRR 25.4 · 95% clinician | no trial data cached |
| Linear iga disease | 37 | 39.8 28.7–55.1ROR 39.9 · χ² 1,329 / p 3e-291 | 38.2 EB05 28.9 · IC025 +4.1 3/3 methods agree | Not in label — unassessed | serious n=37 · ♀ 74% (drug 49%) · 100% clinician | no trial data cached |
| Dysbiosis | 17 | 37.9 23.5–61.3ROR 38.0 · χ² 562 / p 1e-124 | 35.8 EB05 23.6 · IC025 +3.4 3/3 methods agree | Not in label — unassessed | serious n=17 | no trial data cached |
| Urticarial vasculitis | 11 | 37.8 20.8–68.7ROR 37.9 · χ² 351 / p 2e-78 | 35.0 EB05 20.8 · IC025 +2.8 3/3 methods agree | Not in label — unassessed | serious n=11 | 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) | 702 | 6.2 5.7–6.6ROR 6.5 · χ² 3,042 / p <1e-300 | 6.1 EB05 5.7 · IC025 +2.5 3/3 methods agree | Not in label — unassessed | serious PRR 4.3 · 93% clinician | no trial data cached |
| Drug ineffective (drug did not work) | 668 | 0.9 0.8–1.0ROR 0.9 · χ² 10 / p 8e-4 | 0.9 EB05 0.8 · IC025 -0.3 PRR-only: not supported by EBGM or IC | Reporting / coding artifact | serious PRR 1.4 · 90% clinician | no trial data cached |
| Anaphylactic reaction (severe allergic reaction) | 644 | 20.8 19.2–22.4ROR 21.9 · χ² 11,975 / p <1e-300 | 20.5 EB05 19.2 · IC025 +4.2 3/3 methods agree | Labeled (related wording) related wording | serious PRR 12.6 · 93% clinician | no trial data cached |
| Anaphylactic shock | 601 | 42.0 38.8–45.5ROR 44.2 · χ² 23,479 / p <1e-300 | 41.0 EB05 38.3 · IC025 +5.2 3/3 methods agree | Not in label — unassessed | serious PRR 25.4 · 95% clinician | no trial data cached |
| Rash | 592 | 2.4 2.2–2.6ROR 2.5 · χ² 487 / p 3e-108 | 2.4 EB05 2.2 · IC025 +1.1 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 3.0 | no trial data cached |
| Pyrexia (fever) | 512 | 2.6 2.4–2.8ROR 2.7 · χ² 506 / p 2e-112 | 2.6 EB05 2.4 · IC025 +1.2 3/3 methods agree | Labeled (related wording) related wording | serious PRR 1.9 | no trial data cached |
| Renal failure (kidney failure) | 488 | 6.4 5.9–7.0ROR 6.6 · χ² 2,226 / p <1e-300 | 6.3 EB05 5.9 · IC025 +2.5 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 4.0 | no trial data cached |
| Acute kidney injury (sudden kidney damage) | 432 | 5.0 4.5–5.5ROR 5.1 · χ² 1,374 / p <1e-300 | 4.9 EB05 4.6 · IC025 +2.1 3/3 methods agree | Labeled (related wording) related wording | serious PRR 3.0 | no trial data cached |
| Pain | 414 | 1.2 1.1–1.3ROR 1.2 · χ² 11 / p 4e-4 | 1.2 EB05 1.1 · IC025 +0.1 | Not in label — unassessed | serious PRR 1.1 | no trial data cached |
| Off label use (used outside approved label) | 413 | 0.8 0.8–0.9ROR 0.8 · χ² 14 / p 8e-5 | 0.8 EB05 0.8 · IC025 -0.4 PRR-only: not supported by EBGM or IC | Reporting / coding artifact | serious PRR 0.9 | no trial data cached |
| Nausea | 377 | 0.8 0.8–0.9ROR 0.8 · χ² 12 / p 2e-4 | 0.8 EB05 0.8 · IC025 -0.4 PRR-only: not supported by EBGM or IC | Labeled adverse reaction exact term | serious PRR 0.9 | no trial data cached |
| Urticaria (hives) | 351 | 3.7 3.3–4.1ROR 3.8 · χ² 692 / p 9e-153 | 3.7 EB05 3.4 · IC025 +1.7 3/3 methods agree | Not in label — unassessed | serious PRR 4.2 | no trial data cached |
| Dyspnoea (shortness of breath) | 334 | 1.0 0.9–1.1ROR 1.0 · χ² 0 / p 0.280 | 1.0 EB05 0.9 · IC025 -0.1 PRR-only: not supported by EBGM or IC | Not in label — unassessed | serious PRR 0.8 | no trial data cached |
| Drug hypersensitivity | 329 | 3.0 2.7–3.3ROR 3.0 · χ² 431 / p 6e-96 | 3.0 EB05 2.7 · IC025 +1.4 3/3 methods agree | Labeled (related wording) related wording | serious PRR 3.4 · ♀ 70% (drug 49%) | no trial data cached |
| Erythema (skin redness) | 318 | 2.7 2.4–3.0ROR 2.8 · χ² 345 / p 2e-77 | 2.7 EB05 2.5 · IC025 +1.2 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 3.5 | 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=83, PRR 2,238.4
- Thymus hypoplasia — n=81, PRR 1,570.8
- Hypoprothrombinaemia — n=64, PRR 470.1
- Disseminated aspergillosis — n=78, PRR 349.7
- Vitamin k deficiency — n=41, PRR 201.0
- Inspiratory capacity decreased — n=27, PRR 190.2
- Vancomycin infusion reaction — n=22, PRR 112.7
- Incision site infection — n=44, PRR 87.9
- Procedural hypotension — n=30, PRR 63.5
- Kounis syndrome — n=77, PRR 61.7
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 Cefazolin?
In FDA FAERS, the most frequently co-reported reaction terms for Cefazolin are hypotension, anaphylactic reaction, anaphylactic shock, rash, pyrexia, renal failure. 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 Cefazolin have an FDA boxed warning?
No. The FDA label retrieved for Cefazolin has no boxed warning; see the label's Warnings and Precautions for the recognised risks.
Do FAERS signals prove that Cefazolin 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 1367568c-7d27-479f-a4c5-58e99942f686, effective 20251101; matched on
openfda.generic_name.exact:"CEFAZOLIN") - 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, 1,101 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.