Zoledronic Acid side effects: what 39,894 FDA adverse event reports show
Drug class
Bisphosphonate
Who reports
39,894 reports · 87% serious · 5,134 with death outcome · 75% female
Used for
Zoledronic acid injection is a bisphosphonate indicated for: •Treatment and prevention of postmenopausal osteoporosis (1.1, 1.2) •Treatment to increase bone mass in men with osteoporosis (1.3) •Treatment and prevention of glucocorticoid-induced osteoporosis (1.4) •Treatment of Paget’s disease of bone in men and women (1.5) Limitations of Use Optimal duration of use has not been determined.
What it is
Zoledronic acid injection contains zoledronic acid, a bisphosphonic acid which is an inhibitor of osteoclastic bone resorption. Zoledronic acid is designated chemically as (1-Hydroxy-2-imidazo.
Boxed warning
None in the current label
Causality screen of the 40 strongest signals
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.
- 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, for the 300 most-reported drugs, adjusted for age band), and flags pairs whose reports are unusually skewed by sex or come mostly from consumers. Each row also shows the PRR against the other drugs of the same FDA class, which removes most confounding by the condition being treated, and a calibrated p-value: on validation, known non-causes average an ROR of about 2, so significance is judged against that empirical null (✓ = p < 0.05 after calibration). 1,175 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 |
|---|---|---|---|---|---|---|
| Acute phase reaction | 129 | 278.2 224.6–344.4ROR 279.1 · calibrated p 3e-11 ✓ | 176.6 EB05 152.4 · IC025 +6.4 3/3 methods agree | Labeled adverse reaction exact term | serious n=120 | not reported in cached trials |
| Osteopetrosis | 45 | 211.7 149.7–299.4ROR 211.9 · calibrated p 7e-10 ✓ | 141.6 EB05 110.2 · IC025 +5.3 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=45 · ♀ 51% (drug 75%) · 100% clinician | not reported in cached trials |
| Bone sequestrum | 41 | 191.1 133.6–273.4ROR 191.3 · calibrated p 2e-9 ✓ | 131.4 EB05 101.0 · IC025 +5.2 3/3 methods agree | Not in label — unassessed | serious n=39 · 100% clinician | not reported in cached trials |
| Parophthalmia | 61 | 182.5 136.3–244.3ROR 182.7 · calibrated p 2e-9 ✓ | 129.8 EB05 104.7 · IC025 +5.6 3/3 methods agree | Not in label — unassessed | serious n=58 · 100% clinician | not reported in cached trials |
| Idiopathic orbital inflammation | 46 | 167.6 120.2–233.7ROR 167.8 · calibrated p 5e-9 ✓ | 120.6 EB05 94.1 · IC025 +5.3 3/3 methods agree | Labeled (related wording) related wording | serious n=46 · 100% clinician | not reported in cached trials |
| Oroantral fistula | 51 | 160.0 116.9–218.9ROR 160.2 · calibrated p 6e-9 ✓ | 117.2 EB05 92.6 · IC025 +5.3 3/3 methods agree | Not in label — unassessed | serious n=50 · ♀ 43% (drug 75%) · 100% clinician | not reported in cached trials |
| Wound closure | 42 | 143.9 102.3–202.6ROR 144.1 · calibrated p 2e-8 ✓ | 107.4 EB05 82.8 · IC025 +5.1 3/3 methods agree | Not in label — unassessed | serious n=42 · ♀ 52% (drug 75%) · 100% clinician | not reported in cached trials |
| Jaw fistula | 27 | 135.7 88.8–207.2ROR 135.7 · calibrated p 4e-8 ✓ | 100.2 EB05 72.3 · IC025 +4.6 3/3 methods agree | Not in label — unassessed | serious n=27 · ♀ 0% (drug 75%) · 100% clinician | NCT00127205: 1/2,186 (0.0%) on Zoledronic Acid (serious AE) |
| Parathyroid tumour malignant | 25 | 125.6 81.1–194.4ROR 125.7 · calibrated p 8e-8 ✓ | 94.2 EB05 67.1 · IC025 +4.4 3/3 methods agree | Not in label — unassessed | serious n=25 · 100% clinician | not reported in cached trials |
| Amaurosis fugax | 194 | 116.5 99.7–136.1ROR 117.0 · calibrated p 4e-8 ✓ | 94.4 EB05 83.8 · IC025 +6.0 3/3 methods agree | Not in label — unassessed | serious n=194 · 95% clinician | not reported in cached trials |
| Hyperbaric oxygen therapy | 26 | 96.8 63.7–147.1ROR 96.9 · calibrated p 4e-7 ✓ | 77.2 EB05 55.4 · IC025 +4.4 3/3 methods agree | Reporting / coding artifact | serious n=26 · 100% clinician | not reported in cached trials |
| Osteotomy | 48 | 90.3 66.5–122.7ROR 90.4 · calibrated p 4e-7 ✓ | 74.8 EB05 58.7 · IC025 +5.0 3/3 methods agree | Not in label — unassessed | serious n=48 · ♀ 54% (drug 75%) · 100% clinician | not reported in cached trials |
| Oral cavity fistula | 72 | 89.4 69.6–114.7ROR 89.5 · calibrated p 4e-7 ✓ | 74.9 EB05 61.5 · IC025 +5.3 3/3 methods agree | Not in label — unassessed | serious n=72 · 100% clinician | not reported in cached trials |
| Carbohydrate antigen 15-3 increased | 106 | 84.9 69.2–104.3ROR 85.1 · calibrated p 5e-7 ✓ | 72.2 EB05 61.4 · IC025 +5.4 3/3 methods agree | Lab value / disease marker | serious n=104 · ♀ 100% (drug 75%) | not reported in cached trials |
| Periorbital inflammation | 30 | 79.6 54.2–116.9ROR 79.7 · calibrated p 1e-6 ✓ | 66.3 EB05 48.7 · IC025 +4.4 3/3 methods agree | Not in label — unassessed | serious n=29 · 100% clinician | not reported in cached trials |
| Osteonecrosis of external auditory canal | 24 | 76.7 49.9–117.7ROR 76.7 · calibrated p 2e-6 ✓ | 63.7 EB05 45.0 · IC025 +4.2 3/3 methods agree | Not in label — unassessed | serious n=24 · 100% clinician | not reported in cached trials |
| Exposed bone in jaw | 247 | 66.7 58.5–76.2ROR 67.2 · calibrated p 2e-6 ✓ | 59.0 EB05 53.1 · IC025 +5.5 3/3 methods agree | Labeled (related wording) related wording | serious n=244 · 96% clinician | not reported in cached trials |
| Osteonecrosis of jaw (jawbone death) | 2,708 | 64.0 61.6–66.6ROR 68.6 · calibrated p 2e-6 ✓ | 57.1 EB05 55.3 · IC025 +5.8 3/3 methods agree | Labeled (related wording) related wording | serious PRR 37.8 · 95% clinician | NCT00127205: 13/2,125 (0.6%) on Zoledronic Acid (serious AE) |
| Bone debridement | 53 | 63.9 48.1–85.0ROR 64.0 · calibrated p 4e-6 ✓ | 55.9 EB05 44.4 · IC025 +4.8 3/3 methods agree | Not in label — unassessed | serious n=53 · 100% clinician | not reported in cached trials |
| Sequestrectomy | 73 | 63.9 50.1–81.5ROR 64.0 · calibrated p 4e-6 ✓ | 56.2 EB05 46.2 · IC025 +5.0 3/3 methods agree | Not in label — unassessed | serious n=73 · 100% clinician | not reported in cached trials |
| Pik3ca-activated mutation | 33 | 59.1 41.2–84.7ROR 59.1 · calibrated p 9e-6 ✓ | 51.6 EB05 38.5 · IC025 +4.3 3/3 methods agree | Not in label — unassessed | serious n=33 · 100% clinician | not reported in cached trials |
| Hormone receptor positive her2 negative breast cancer | 30 | 55.4 38.1–80.8ROR 55.5 · calibrated p 1e-5 ✓ | 48.7 EB05 35.8 · IC025 +4.2 3/3 methods agree | Not in label — unassessed | serious n=30 · ♀ 100% (drug 75%) · 100% clinician | not reported in cached trials |
| Atypical femur fracture | 247 | 50.1 44.0–57.0ROR 50.4 · calibrated p 1e-5 ✓ | 45.6 EB05 41.0 · IC025 +5.2 3/3 methods agree | Labeled adverse reaction exact term | serious n=246 · 95% clinician | not reported in cached trials |
| Atypical fracture | 51 | 47.6 35.8–63.5ROR 47.7 · calibrated p 3e-5 ✓ | 43.1 EB05 34.0 · IC025 +4.5 3/3 methods agree | Labeled adverse reaction exact term | serious n=50 · 100% clinician | not reported in cached trials |
| Debridement | 62 | 46.2 35.6–59.8ROR 46.2 · calibrated p 3e-5 ✓ | 42.0 EB05 33.9 · IC025 +4.6 3/3 methods agree | Not in label — unassessed | serious n=62 · 100% clinician | not reported in cached trials |
| Primary sequestrum | 67 | 41.3 32.2–53.0ROR 41.4 · calibrated p 5e-5 ✓ | 38.0 EB05 30.9 · IC025 +4.5 3/3 methods agree | Not in label — unassessed | serious n=67 · 100% clinician | not reported in cached trials |
| Actinomycosis | 69 | 40.4 31.6–51.6ROR 40.5 · calibrated p 6e-5 ✓ | 37.2 EB05 30.4 · IC025 +4.5 3/3 methods agree | Not in label — unassessed | serious n=69 · 100% clinician | not reported in cached trials |
| Osteolysis | 135 | 37.0 31.1–44.0ROR 37.1 · calibrated p 9e-5 ✓ | 34.4 EB05 29.8 · IC025 +4.7 3/3 methods agree | Not in label — unassessed | serious n=134 | not reported in cached trials |
| Bone lesion | 236 | 36.7 32.2–41.9ROR 36.9 · calibrated p 9e-5 ✓ | 34.3 EB05 30.8 · IC025 +4.8 3/3 methods agree | Not in label — unassessed | serious n=233 | not reported in cached trials |
| Bone marrow infiltration | 24 | 34.8 23.0–52.6ROR 34.8 · calibrated p 2e-4 ✓ | 31.9 EB05 22.6 · IC025 +3.6 3/3 methods agree | Not in label — unassessed | serious n=24 · ♀ 100% (drug 75%) · 100% clinician | not reported in cached trials |
| Metastases to bone | 927 | 31.5 29.5–33.7ROR 32.2 · calibrated p 2e-4 ✓ | 29.8 EB05 28.2 · IC025 +4.8 3/3 methods agree | Not in label — unassessed | serious PRR 19.9 | not reported in cached trials |
| Dental fistula | 23 | 30.5 20.0–46.5ROR 30.5 · calibrated p 4e-4 ✓ | 28.3 EB05 19.8 · IC025 +3.5 3/3 methods agree | Not in label — unassessed | serious n=23 | not reported in cached trials |
| Respiratory tract infection bacterial | 27 | 29.9 20.3–44.1ROR 29.9 · calibrated p 4e-4 ✓ | 27.8 EB05 20.1 · IC025 +3.6 3/3 methods agree | Labeled (related wording) related wording | serious n=27 · ♀ 0% (drug 75%) · 100% clinician | not reported in cached trials |
| Osteosclerosis | 85 | 29.9 24.0–37.2ROR 29.9 · calibrated p 3e-4 ✓ | 28.1 EB05 23.5 · IC025 +4.2 3/3 methods agree | Not in label — unassessed | serious n=83 | not reported in cached trials |
| Metastases to bone marrow | 27 | 29.7 20.2–43.8ROR 29.7 · calibrated p 4e-4 ✓ | 27.7 EB05 20.0 · IC025 +3.6 3/3 methods agree | Not in label — unassessed | serious n=27 · ♀ 100% (drug 75%) · 100% clinician | not reported in cached trials |
| Fanconi syndrome | 75 | 29.6 23.4–37.3ROR 29.6 · calibrated p 3e-4 ✓ | 27.9 EB05 23.0 · IC025 +4.2 3/3 methods agree | Not in label — unassessed | serious n=75 · 100% clinician | not reported in cached trials |
| Iridocyclitis | 161 | 28.5 24.3–33.4ROR 28.6 · calibrated p 4e-4 ✓ | 27.0 EB05 23.7 · IC025 +4.4 3/3 methods agree | Labeled adverse reaction exact term | serious n=158 · 94% clinician | not reported in cached trials |
| Metastases to spine | 167 | 27.5 23.6–32.1ROR 27.6 · calibrated p 4e-4 ✓ | 26.1 EB05 22.9 · IC025 +4.3 3/3 methods agree | Not in label — unassessed | serious n=167 | not reported in cached trials |
| Giant cell arteritis | 40 | 27.3 19.9–37.6ROR 27.4 · calibrated p 6e-4 ✓ | 25.7 EB05 19.7 · IC025 +3.8 3/3 methods agree | Not in label — unassessed | serious n=38 · ♀ 100% (drug 75%) · 100% clinician | not reported in cached trials |
| Metastases to pelvis | 30 | 26.2 18.1–37.8ROR 26.2 · calibrated p 8e-4 ✓ | 24.6 EB05 18.1 · IC025 +3.6 3/3 methods agree | Not in label — unassessed | serious n=30 · ♀ 100% (drug 75%) | 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 Zoledronic Acid 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 (2 of 40 signal terms matched).
- NCT00127205 — S0307 Phase III Trial of Bisphosphonates as Adjuvant Therapy for Primary Breast Cancer. (N=6097, PHASE3; 230 AE terms posted; arms: Arm I Zoledronic Acid; Arm II Clodronate; Arm III Ibandronate)
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 |
|---|---|---|---|---|---|---|
| Arthralgia (joint pain) | 3,220 | 4.1 4.0–4.2ROR 4.4 · calibrated p 0.314 | 4.1 EB05 4.0 · IC025 +2.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 4.1 | not reported in cached trials |
| Pain | 3,151 | 2.7 2.6–2.8ROR 2.8 · calibrated p 0.679 | 2.7 EB05 2.6 · IC025 +1.4 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 2.4 | NCT00127205: 3/2,186 (0.1%) on Zoledronic Acid (serious AE) |
| Nausea | 2,818 | 1.9 1.8–1.9ROR 1.9 · calibrated p 0.915 | 1.9 EB05 1.8 · IC025 +0.8 | Labeled adverse reaction exact term | serious PRR 2.0 | NCT00127205: 2/2,186 (0.1%) on Zoledronic Acid (serious AE) |
| Pyrexia (fever) | 2,811 | 4.3 4.1–4.4ROR 4.5 · calibrated p 0.290 | 4.3 EB05 4.1 · IC025 +2.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 3.2 | not reported in cached trials |
| Fatigue (tiredness) | 2,799 | 1.9 1.8–2.0ROR 2.0 · calibrated p 0.924 | 1.9 EB05 1.8 · IC025 +0.9 | Labeled adverse reaction exact term | serious PRR 2.0 | NCT00127205: 4/2,186 (0.2%) on Zoledronic Acid (serious AE) |
| Osteonecrosis of jaw (jawbone death) | 2,708 | 64.0 61.6–66.6ROR 68.6 · calibrated p 2e-6 ✓ | 57.1 EB05 55.3 · IC025 +5.8 3/3 methods agree | Labeled (related wording) related wording | serious PRR 37.8 · 95% clinician | NCT00127205: 13/2,125 (0.6%) on Zoledronic Acid (serious AE) |
| Death | 2,497 | 1.5 1.5–1.6ROR 1.6 · calibrated p 0.681 | 1.5 EB05 1.5 · IC025 +0.5 | Outcome field, not a reaction | serious PRR 1.0 | NCT00127205: 1/2,186 (0.0%) on Zoledronic Acid (serious AE) |
| Headache | 2,365 | 2.0 1.9–2.1ROR 2.1 · calibrated p 0.971 | 2.0 EB05 1.9 · IC025 +0.9 | Labeled adverse reaction exact term | serious PRR 2.2 | NCT00127205: 7/2,186 (0.3%) on Zoledronic Acid (serious AE) |
| Diarrhoea (diarrhea) | 2,277 | 1.9 1.8–1.9ROR 1.9 · calibrated p 0.897 | 1.9 EB05 1.8 · IC025 +0.8 | Labeled adverse reaction exact term | serious PRR 1.9 | NCT00127205: 4/2,186 (0.2%) on Zoledronic Acid (serious AE) |
| Vomiting | 2,061 | 2.3 2.2–2.4ROR 2.4 · calibrated p 0.863 | 2.3 EB05 2.2 · IC025 +1.1 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 2.1 | NCT00127205: 2/2,186 (0.1%) on Zoledronic Acid (serious AE) |
| Asthenia (weakness) | 1,971 | 2.8 2.6–2.9ROR 2.9 · calibrated p 0.675 | 2.8 EB05 2.7 · IC025 +1.4 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 2.3 | NCT00127205: 4/2,186 (0.2%) on Zoledronic Acid (serious AE) |
| Myalgia (muscle pain) | 1,866 | 5.8 5.6–6.1ROR 6.1 · calibrated p 0.146 | 5.8 EB05 5.5 · IC025 +2.4 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 5.6 | not reported in cached trials |
| Off label use (used outside approved label) | 1,752 | 1.1 1.0–1.1ROR 1.1 · calibrated p 0.348 | 1.1 EB05 1.0 · IC025 +0.0 | Reporting / coding artifact | serious PRR 1.2 | not reported in cached trials |
| Pain in extremity | 1,676 | 3.0 2.9–3.1ROR 3.1 · calibrated p 0.600 | 3.0 EB05 2.9 · IC025 +1.5 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 2.8 | not reported in cached trials |
| Dyspnoea (shortness of breath) | 1,653 | 1.5 1.5–1.6ROR 1.6 · calibrated p 0.681 | 1.5 EB05 1.5 · IC025 +0.5 | Labeled adverse reaction exact term | serious PRR 1.3 | NCT00127205: 10/2,186 (0.5%) on Zoledronic Acid (serious AE) |
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.
- Bone sequestrum — n=41, PRR 191.1
- Parophthalmia — n=61, PRR 182.5
- Oroantral fistula — n=51, PRR 160.0
- Wound closure — n=42, PRR 143.9
- Jaw fistula — n=27, PRR 135.7 (also seen in trial arm)
- Parathyroid tumour malignant — n=25, PRR 125.6
- Amaurosis fugax — n=194, PRR 116.5
- Osteotomy — n=48, PRR 90.3
- Oral cavity fistula — n=72, PRR 89.4
- Periorbital inflammation — n=30, PRR 79.6
✓ A hand-written Bradford Hill causality assessment exists for this drug: Zoledronic acid (bisphosphonates) ↔ Osteonecrosis of the jaw.
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 Zoledronic Acid?
In FDA FAERS, the most frequently co-reported reaction terms for Zoledronic Acid are arthralgia, pain, nausea, pyrexia, fatigue, osteonecrosis of jaw. 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 Zoledronic Acid have an FDA boxed warning?
No. The FDA label retrieved for Zoledronic Acid has no boxed warning; see the label's Warnings and Precautions for the recognised risks.
Do FAERS signals prove that Zoledronic Acid 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 16fcf8c9-ef8a-4e93-9ee6-acfadd35a861, effective 20230921; matched on
openfda.generic_name.exact:"ZOLEDRONIC ACID") - 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, 1,215 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
ZOLEDRONIC ACID, results-bearing studies sorted by enrollment)
Page generated 2026-10-14. 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.