Drug · FAERS side-effect profile with label screen
Azithromycin side effects: what 58,299 FDA adverse event reports show
Drug class
Macrolide antibacterial drug
FDA label, Indications wording
Who reports
58,299 reports · 75% serious · 5,236 with death outcome · 61% female
openFDA FAERS counts, all years, deduplication not applied
Used for
Azithromycin tablet is a macrolide antibacterial drug indicated for treatment of patients with mild to moderate infections caused by susceptible strains of the designated microorganisms in the specific conditions listed below: Acute bacterial exacerbat.
FDA label, Indications and Usage
What it is
Azithromycin tablets USP contain the active ingredient azithromycin, a macrolide antibacterial drug, for oral administration. Azithromycin has the chemical name (2R,3S,4R,5R,8R,10R,11R,12S,13S.
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 (related wording) 3Likely indication confounding 7Reporting / coding artifact 1Lab value / disease marker 3Not in label — unassessed 26
What the badges mean
- Labeled (related wording) The label describes this effect under different wording (e.g. 'neutropenia' for 'neutrophil count decreased'). Treated as known.
- 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. 1,197 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 |
|---|---|---|---|---|---|---|
| Normal labour | 123 | 2,720.2 1,615.9–4,579.2ROR 2,725.9 · χ² 38,172 / p <1e-300 | 299.4 EB05 257.5 · IC025 +6.8 3/3 methods agree | Not in label — unassessed | serious n=123 · ♀ 100% (drug 61%) · 100% clinician | not reported in cached trials |
| Vaginal flatulence | 169 | 449.6 358.3–564.2ROR 450.9 · χ² 33,118 / p <1e-300 | 194.2 EB05 170.9 · IC025 +6.7 3/3 methods agree | Not in label — unassessed | serious n=169 · ♀ 100% (drug 61%) | not reported in cached trials |
| Congenital hiatus hernia | 112 | 370.4 284.2–482.7ROR 371.1 · χ² 19,978 / p <1e-300 | 176.1 EB05 150.4 · IC025 +6.3 3/3 methods agree | Not in label — unassessed | serious n=112 · ♀ 0% (drug 61%) · 100% clinician | not reported in cached trials |
| Total lung capacity increased | 118 | 274.7 216.0–349.3ROR 275.2 · χ² 17,961 / p <1e-300 | 151.3 EB05 129.8 · IC025 +6.2 3/3 methods agree | Not in label — unassessed | serious n=118 · ♀ 100% (drug 61%) · 100% clinician | not reported in cached trials |
| Pulmonary vasculitis | 189 | 200.8 168.0–240.0ROR 201.5 · χ² 23,846 / p <1e-300 | 126.9 EB05 112.4 · IC025 +6.3 3/3 methods agree | Not in label — unassessed | serious n=189 · ♀ 0% (drug 61%) | not reported in cached trials |
| Total lung capacity abnormal | 134 | 195.9 158.7–241.9ROR 196.4 · χ² 16,601 / p <1e-300 | 124.3 EB05 107.6 · IC025 +6.1 3/3 methods agree | Not in label — unassessed | serious n=133 · ♀ 0% (drug 61%) | not reported in cached trials |
| Asthma-chronic obstructive pulmonary disease overlap syndrome | 155 | 152.8 126.6–184.4ROR 153.2 · χ² 16,218 / p <1e-300 | 105.6 EB05 92.4 · IC025 +6.1 3/3 methods agree | Not in label — unassessed | serious n=155 | not reported in cached trials |
| Capillaritis | 60 | 103.6 77.7–138.1ROR 103.7 · χ² 4,635 / p <1e-300 | 78.4 EB05 63.1 · IC025 +5.2 3/3 methods agree | Not in label — unassessed | serious n=60 · ♀ 0% (drug 61%) | not reported in cached trials |
| Spirometry abnormal | 119 | 91.3 74.7–111.7ROR 91.5 · χ² 8,380 / p <1e-300 | 72.0 EB05 61.8 · IC025 +5.5 3/3 methods agree | Lab value / disease marker | serious n=119 · ♀ 0% (drug 61%) | not reported in cached trials |
| Delivery | 133 | 90.3 74.7–109.3ROR 90.5 · χ² 9,289 / p <1e-300 | 71.5 EB05 61.8 · IC025 +5.5 3/3 methods agree | Not in label — unassessed | serious n=127 · ♀ 100% (drug 61%) · 90% clinician | not reported in cached trials |
| Mite allergy | 115 | 79.0 64.6–96.7ROR 79.2 · χ² 7,177 / p <1e-300 | 64.1 EB05 54.9 · IC025 +5.4 3/3 methods agree | Not in label — unassessed | serious n=114 · ♀ 0% (drug 61%) | not reported in cached trials |
| Mycotic allergy | 114 | 56.2 46.1–68.4ROR 56.3 · χ² 5,285 / p <1e-300 | 48.3 EB05 41.3 · IC025 +5.0 3/3 methods agree | Not in label — unassessed | serious n=112 · ♀ 0% (drug 61%) | not reported in cached trials |
| Antineutrophil cytoplasmic antibody positive | 94 | 53.2 42.9–66.1ROR 53.3 · χ² 4,141 / p <1e-300 | 46.0 EB05 38.7 · IC025 +4.9 3/3 methods agree | Lab value / disease marker | serious n=94 · ♀ 0% (drug 61%) | not reported in cached trials |
| Mycobacterium avium complex infection | 341 | 52.8 47.1–59.1ROR 53.1 · χ² 15,031 / p <1e-300 | 46.0 EB05 42.0 · IC025 +5.3 3/3 methods agree | Not in label — unassessed | serious n=330 | not reported in cached trials |
| Mycobacterium abscessus infection | 89 | 51.9 41.5–64.8ROR 52.0 · χ² 3,829 / p <1e-300 | 45.0 EB05 37.7 · IC025 +4.8 3/3 methods agree | Not in label — unassessed | serious n=88 · 100% clinician | not reported in cached trials |
| Dust allergy | 120 | 51.0 42.2–61.8ROR 51.1 · χ² 5,101 / p <1e-300 | 44.4 EB05 38.2 · IC025 +4.9 3/3 methods agree | Not in label — unassessed | serious n=120 · ♀ 0% (drug 61%) | not reported in cached trials |
| Neuritis | 185 | 49.1 42.1–57.2ROR 49.2 · χ² 7,609 / p <1e-300 | 43.0 EB05 38.1 · IC025 +5.0 3/3 methods agree | Not in label — unassessed | serious n=183 · ♀ 0% (drug 61%) | not reported in cached trials |
| Bronchopulmonary aspergillosis allergic | 110 | 49.0 40.1–59.8ROR 49.1 · χ² 4,498 / p <1e-300 | 42.8 EB05 36.5 · IC025 +4.9 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=109 | not reported in cached trials |
| Female genital tract fistula | 176 | 40.9 35.0–47.8ROR 41.0 · χ² 6,104 / p <1e-300 | 36.6 EB05 32.3 · IC025 +4.8 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=176 · ♀ 100% (drug 61%) | not reported in cached trials |
| Pulmonary function test abnormal | 154 | 39.3 33.2–46.4ROR 39.4 · χ² 5,134 / p <1e-300 | 35.3 EB05 30.9 · IC025 +4.7 3/3 methods agree | Reporting / coding artifact | serious n=153 | not reported in cached trials |
| Abortion incomplete | 170 | 35.5 30.4–41.6ROR 35.6 · χ² 5,153 / p <1e-300 | 32.3 EB05 28.4 · IC025 +4.6 3/3 methods agree | Not in label — unassessed | serious n=47 · ♀ 100% (drug 61%) · 100% clinician | not reported in cached trials |
| Conjunctivitis allergic | 131 | 35.3 29.5–42.2ROR 35.4 · χ² 3,939 / p <1e-300 | 32.1 EB05 27.7 · IC025 +4.6 3/3 methods agree | Labeled (related wording) related wording | serious n=130 · ♀ 0% (drug 61%) | not reported in cached trials |
| Bronchiectasis | 596 | 35.3 32.4–38.4ROR 35.6 · χ² 18,025 / p <1e-300 | 32.1 EB05 30.0 · IC025 +4.8 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=592 | not reported in cached trials |
| Chronic sinusitis | 335 | 35.2 31.5–39.4ROR 35.4 · χ² 10,108 / p <1e-300 | 32.1 EB05 29.3 · IC025 +4.8 3/3 methods agree | Likely indication confounding term in indications | serious n=331 · ♀ 91% (drug 61%) | not reported in cached trials |
| Respiratory symptom | 228 | 31.8 27.8–36.4ROR 31.9 · χ² 6,213 / p <1e-300 | 29.2 EB05 26.2 · IC025 +4.6 3/3 methods agree | Labeled (related wording) related wording | serious n=223 · ♀ 0% (drug 61%) | not reported in cached trials |
| Eosinophilic granulomatosis with polyangiitis | 161 | 31.1 26.5–36.5ROR 31.2 · χ² 4,284 / p <1e-300 | 28.6 EB05 25.1 · IC025 +4.5 3/3 methods agree | Not in label — unassessed | serious n=161 · ♀ 0% (drug 61%) | not reported in cached trials |
| Rhinitis allergic | 348 | 30.5 27.4–34.0ROR 30.7 · χ² 9,119 / p <1e-300 | 28.1 EB05 25.7 · IC025 +4.6 3/3 methods agree | Labeled (related wording) related wording | serious n=341 · ♀ 82% (drug 61%) | not reported in cached trials |
| Breath sounds abnormal | 385 | 30.4 27.4–33.7ROR 30.6 · χ² 10,050 / p <1e-300 | 28.0 EB05 25.8 · IC025 +4.6 3/3 methods agree | Not in label — unassessed | serious n=378 | not reported in cached trials |
| Forced expiratory volume decreased | 219 | 30.0 26.2–34.5ROR 30.1 · χ² 5,638 / p <1e-300 | 27.7 EB05 24.8 · IC025 +4.5 3/3 methods agree | Lab value / disease marker | serious n=217 · ♀ 22% (drug 61%) | not reported in cached trials |
| Chronic kidney disease-mineral and bone disorder | 81 | 29.2 23.3–36.6ROR 29.3 · χ² 2,013 / p <1e-300 | 26.9 EB05 22.3 · IC025 +4.2 3/3 methods agree | Not in label — unassessed | serious n=81 | not reported in cached trials |
| Radiculopathy | 197 | 29.0 25.1–33.5ROR 29.1 · χ² 4,892 / p <1e-300 | 26.8 EB05 23.8 · IC025 +4.4 3/3 methods agree | Not in label — unassessed | serious n=196 · ♀ 100% (drug 61%) | not reported in cached trials |
| Proctitis | 189 | 25.9 22.4–30.1ROR 26.0 · χ² 4,198 / p <1e-300 | 24.2 EB05 21.4 · IC025 +4.3 3/3 methods agree | Not in label — unassessed | serious n=189 · ♀ 100% (drug 61%) | not reported in cached trials |
| Biliary dyskinesia | 113 | 25.3 20.9–30.6ROR 25.4 · χ² 2,440 / p <1e-300 | 23.6 EB05 20.2 · IC025 +4.1 3/3 methods agree | Not in label — unassessed | serious n=114 · ♀ 100% (drug 61%) | not reported in cached trials |
| Cystic fibrosis | 361 | 24.9 22.4–27.7ROR 25.0 · χ² 7,717 / p <1e-300 | 23.3 EB05 21.4 · IC025 +4.3 3/3 methods agree | Likely indication confounding term in indications | serious n=352 | not reported in cached trials |
| Bronchial wall thickening | 46 | 24.3 18.0–32.7ROR 24.3 · χ² 940 / p 1e-206 | 22.6 EB05 17.6 · IC025 +3.7 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=45 · ♀ 100% (drug 61%) | not reported in cached trials |
| Hyperparathyroidism secondary | 160 | 24.2 20.6–28.4ROR 24.3 · χ² 3,310 / p <1e-300 | 22.7 EB05 19.9 · IC025 +4.1 3/3 methods agree | Not in label — unassessed | serious n=160 | not reported in cached trials |
| Infective pulmonary exacerbation of cystic fibrosis | 345 | 24.1 21.6–26.9ROR 24.2 · χ² 7,128 / p <1e-300 | 22.6 EB05 20.7 · IC025 +4.3 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=315 | not reported in cached trials |
| Total lung capacity decreased | 99 | 23.6 19.3–29.0ROR 23.7 · χ² 1,991 / p <1e-300 | 22.1 EB05 18.7 · IC025 +4.0 3/3 methods agree | Not in label — unassessed | serious n=98 · ♀ 100% (drug 61%) | not reported in cached trials |
| Nasal polyps | 291 | 23.0 20.5–25.9ROR 23.1 · χ² 5,738 / p <1e-300 | 21.7 EB05 19.6 · IC025 +4.2 3/3 methods agree | Not in label — unassessed | serious n=288 · ♀ 91% (drug 61%) | not reported in cached trials |
| Malignant melanoma in situ | 76 | 23.0 18.3–29.0ROR 23.1 · χ² 1,483 / p <1e-300 | 21.6 EB05 17.8 · IC025 +3.9 3/3 methods agree | Not in label — unassessed | serious n=76 · ♀ 0% (drug 61%) · 100% clinician | not reported in cached trials |
Trial evidence (ClinicalTrials.gov)
✓ Trial adverse-event data found on ClinicalTrials.gov
Largest completed trials with posted results that list Azithromycin as a study intervention. The right-hand column of the signal table shows whether each FAERS term was also recorded in these trials, with a real denominator (0 of 40 signal terms matched).
- NCT04224987 — Azithromycin for Child Survival in Niger: Mortality and Resistance Trial (N=864493, PHASE4; 4 AE terms posted; arms: Azithro 1-11; Azithro 1-59; Placebo)
- NCT02047981 — Mortality Reduction After Oral Azithromycin: Mortality Study (N=190238, PHASE4; 9 AE terms posted; arms: Biannual Mass Oral Azithromycin; Biannual Mass Oral Placebo)
Caveats: trial populations, doses and follow-up differ from the reporting population; AE terms are sponsor-coded and matched here by wording; absence from a trial list means the term was not reported above the sponsor's frequency threshold, not that it cannot occur.
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 |
|---|---|---|---|---|---|---|
| Off label use (used outside approved label) | 5,081 | 2.1 2.1–2.2ROR 2.2 · χ² 3,083 / p <1e-300 | 2.1 EB05 2.1 · IC025 +1.0 3/3 methods agree | Reporting / coding artifact | serious PRR 2.4 | not reported in cached trials |
| Drug ineffective (drug did not work) | 5,032 | 1.4 1.3–1.4ROR 1.4 · χ² 548 / p 1e-121 | 1.4 EB05 1.3 · IC025 +0.4 | Reporting / coding artifact | serious PRR 2.3 | not reported in cached trials |
| Dyspnoea (shortness of breath) | 4,585 | 2.9 2.9–3.0ROR 3.1 · χ² 5,943 / p <1e-300 | 2.9 EB05 2.8 · IC025 +1.5 3/3 methods agree | Not in label — unassessed | serious PRR 2.7 | not reported in cached trials |
| Nausea | 3,437 | 1.6 1.5–1.6ROR 1.6 · χ² 733 / p 9e-162 | 1.6 EB05 1.5 · IC025 +0.6 | Labeled adverse reaction exact term | serious PRR 1.8 | not reported in cached trials |
| Pain | 3,248 | 1.9 1.8–2.0ROR 2.0 · χ² 1,425 / p <1e-300 | 1.9 EB05 1.8 · IC025 +0.9 | Labeled adverse reaction exact term | serious PRR 2.0 | not reported in cached trials |
| Pneumonia (lung infection) | 3,203 | 3.6 3.5–3.7ROR 3.7 · χ² 6,013 / p <1e-300 | 3.6 EB05 3.5 · IC025 +1.8 3/3 methods agree | Likely indication confounding term in indications; also in warnings | serious PRR 2.8 | NCT02047981: 1/97,047 (0.0%) on Azithromycin (serious AE) |
| Cough | 3,062 | 4.0 3.8–4.1ROR 4.1 · χ² 6,811 / p <1e-300 | 3.9 EB05 3.8 · IC025 +1.9 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 4.2 | not reported in cached trials |
| Drug hypersensitivity | 2,971 | 5.6 5.4–5.8ROR 5.8 · χ² 11,070 / p <1e-300 | 5.5 EB05 5.3 · IC025 +2.4 3/3 methods agree | Labeled (related wording) related wording | serious PRR 3.1 | not reported in cached trials |
| Diarrhoea (diarrhea) | 2,930 | 1.6 1.6–1.7ROR 1.7 · χ² 753 / p 5e-166 | 1.6 EB05 1.6 · IC025 +0.7 | Labeled adverse reaction exact term | serious PRR 1.6 | NCT04224987: 1/104,374 (0.0%) on Azithromycin (serious AE) |
| Fatigue (tiredness) | 2,866 | 1.3 1.3–1.4ROR 1.3 · χ² 240 / p 2e-54 | 1.3 EB05 1.3 · IC025 +0.3 | Labeled adverse reaction exact term | serious PRR 1.5 | not reported in cached trials |
| Headache | 2,609 | 1.5 1.4–1.6ROR 1.5 · χ² 447 / p 2e-99 | 1.5 EB05 1.5 · IC025 +0.5 | Labeled adverse reaction exact term | serious PRR 1.8 | not reported in cached trials |
| Pyrexia (fever) | 2,368 | 2.5 2.4–2.6ROR 2.5 · χ² 2,090 / p <1e-300 | 2.5 EB05 2.4 · IC025 +1.2 3/3 methods agree | Labeled (related wording) related wording | serious PRR 2.1 | not reported in cached trials |
| Vomiting | 2,285 | 1.8 1.7–1.8ROR 1.8 · χ² 757 / p 7e-167 | 1.8 EB05 1.7 · IC025 +0.7 | Labeled adverse reaction exact term | serious PRR 1.6 | NCT04224987: 1/104,374 (0.0%) on Azithromycin (serious AE) |
| Anxiety | 2,242 | 2.8 2.7–3.0ROR 2.9 · χ² 2,687 / p <1e-300 | 2.8 EB05 2.7 · IC025 +1.4 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 2.9 | not reported in cached trials |
| Condition aggravated | 2,155 | 2.6 2.5–2.7ROR 2.6 · χ² 2,094 / p <1e-300 | 2.6 EB05 2.5 · IC025 +1.3 3/3 methods agree | Reporting / coding artifact | serious PRR 2.7 | not reported in cached trials |
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.
- Normal labour — n=123, PRR 2,720.2
- Vaginal flatulence — n=169, PRR 449.6
- Congenital hiatus hernia — n=112, PRR 370.4
- Total lung capacity increased — n=118, PRR 274.7
- Pulmonary vasculitis — n=189, PRR 200.8
- Total lung capacity abnormal — n=134, PRR 195.9
- Asthma-chronic obstructive pulmonary disease overlap syndrome — n=155, PRR 152.8
- Capillaritis — n=60, PRR 103.6
- Delivery — n=133, PRR 90.3
- Mite allergy — n=115, PRR 79.0
✓ A hand-written Bradford Hill causality assessment exists for this drug: Azithromycin (macrolides) ↔ QT prolongation / torsades.
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 Azithromycin?
In FDA FAERS, the most frequently co-reported reaction terms for Azithromycin are dyspnoea, nausea, pain, pneumonia, cough, drug hypersensitivity. 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 Azithromycin have an FDA boxed warning?
No. The FDA label retrieved for Azithromycin has no boxed warning; see the label's Warnings and Precautions for the recognised risks.
Do FAERS signals prove that Azithromycin 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 01649d79-4677-4577-a3e4-e054f3f9fc3b, effective 20260820; matched on
openfda.generic_name.exact:"AZITHROMYCIN") - 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, 1,237 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 - ClinicalTrials.gov API v2 (query
AZITHROMYCIN, results-bearing studies sorted by enrollment)
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.