Meclizine 25Mg side effects: what 13,547 FDA adverse event reports show
Drug class
Not stated in label
Label matched
Meclizine Hcl 25Mg (Meclizine)
Who reports
13,547 reports · 65% serious · 1,286 with death outcome · 74% female
Used for
prevents and treats nausea, vomiting or dizziness associated with motion sickness
Boxed warning
None in the current label
Causality screen of the 40 strongest signals
What the badges mean
- 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.
- 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.
- No label text to screen No validated FDA label was retrievable for this product, so the screen could not run. Disproportionality only.
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. 1,106 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 |
|---|---|---|---|---|---|---|
| Narcotic bowel syndrome | 16 | 176.9 105.5–296.8ROR 177.1 · χ² 2,353 / p <1e-300 | 133.7 EB05 87.3 · IC025 +3.9 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=16 | not reported in cached trials |
| Echolalia | 18 | 92.2 57.3–148.3ROR 92.3 · χ² 1,446 / p <1e-300 | 79.9 EB05 53.4 · IC025 +3.9 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=18 | not reported in cached trials |
| Chronic kidney disease-mineral and bone disorder | 42 | 62.8 46.2–85.5ROR 63.0 · χ² 2,395 / p <1e-300 | 58.8 EB05 45.4 · IC025 +4.6 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=42 | not reported in cached trials |
| Salivary gland calculus | 14 | 61.4 36.0–104.7ROR 61.4 · χ² 742 / p 9e-164 | 54.9 EB05 34.7 · IC025 +3.4 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=14 | not reported in cached trials |
| Hyperparathyroidism secondary | 93 | 59.0 48.0–72.5ROR 59.4 · χ² 5,048 / p <1e-300 | 56.2 EB05 47.2 · IC025 +5.1 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=93 | not reported in cached trials |
| Nephrogenic anaemia | 166 | 56.9 48.8–66.4ROR 57.6 · χ² 8,743 / p <1e-300 | 54.6 EB05 48.0 · IC025 +5.3 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=166 | not reported in cached trials |
| Rebound acid hypersecretion | 91 | 47.3 38.4–58.2ROR 47.6 · χ² 3,955 / p <1e-300 | 45.5 EB05 38.2 · IC025 +4.9 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=91 | not reported in cached trials |
| Vertigo positional | 27 | 24.3 16.6–35.5ROR 24.3 · χ² 570 / p 3e-126 | 23.5 EB05 17.0 · IC025 +3.4 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=24 | not reported in cached trials |
| Cerumen impaction | 12 | 20.4 11.5–36.0ROR 20.4 · χ² 200 / p 1e-45 | 19.2 EB05 11.2 · IC025 +2.5 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=12 | not reported in cached trials |
| Pleurothotonus | 11 | 18.9 10.4–34.2ROR 18.9 · χ² 167 / p 2e-38 | 17.6 EB05 9.6 · IC025 +2.4 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=11 | not reported in cached trials |
| End stage renal disease | 222 | 18.9 16.5–21.5ROR 19.2 · χ² 3,695 / p <1e-300 | 18.6 EB05 16.7 · IC025 +3.9 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 16.4 | not reported in cached trials |
| Sick sinus syndrome | 14 | 18.8 11.1–31.8ROR 18.8 · χ² 216 / p 4e-49 | 17.9 EB05 10.8 · IC025 +2.6 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=14 | not reported in cached trials |
| Sialoadenitis | 15 | 17.3 10.4–28.7ROR 17.3 · χ² 212 / p 3e-48 | 16.4 EB05 10.0 · IC025 +2.6 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=15 | not reported in cached trials |
| Inner ear disorder | 11 | 16.1 8.9–29.2ROR 16.2 · χ² 140 / p 1e-32 | 14.7 EB05 7.7 · IC025 +2.3 3/3 methods agree | No label text to screen label has no adverse-reaction text | – | not reported in cached trials |
| Chronic kidney disease | 787 | 16.0 15.0–17.2ROR 17.0 · χ² 11,010 / p <1e-300 | 15.9 EB05 15.0 · IC025 +3.9 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 14.2 | not reported in cached trials |
| Aortic dilatation | 11 | 15.7 8.7–28.5ROR 15.8 · χ² 136 / p 1e-31 | 14.2 EB05 7.4 · IC025 +2.2 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=11 | not reported in cached trials |
| Cataplexy | 13 | 14.2 8.2–24.5ROR 14.2 · χ² 145 / p 1e-33 | 12.8 EB05 7.2 · IC025 +2.3 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=12 | not reported in cached trials |
| Colonic polyp | 15 | 14.0 8.4–23.2ROR 14.0 · χ² 166 / p 2e-38 | 12.8 EB05 7.6 · IC025 +2.4 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=15 | not reported in cached trials |
| Carotid artery disease | 11 | 13.4 7.4–24.3ROR 13.5 · χ² 114 / p 8e-27 | 11.7 EB05 6.1 · IC025 +2.1 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=11 | not reported in cached trials |
| Vertigo (spinning dizziness) | 523 | 13.4 12.3–14.6ROR 13.9 · χ² 5,942 / p <1e-300 | 13.3 EB05 12.3 · IC025 +3.6 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 10.8 | not reported in cached trials |
| Excoriation | 21 | 12.7 8.3–19.5ROR 12.7 · χ² 213 / p 1e-48 | 11.9 EB05 7.7 · IC025 +2.6 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=20 | not reported in cached trials |
| Essential hypertension | 21 | 12.6 8.2–19.4ROR 12.7 · χ² 212 / p 3e-48 | 11.8 EB05 7.7 · IC025 +2.6 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=17 | not reported in cached trials |
| Rhonchi | 11 | 12.4 6.8–22.4ROR 12.4 · χ² 103 / p 2e-24 | 10.5 EB05 5.5 · IC025 +2.0 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=11 | not reported in cached trials |
| Neck injury | 22 | 11.6 7.6–17.7ROR 11.6 · χ² 202 / p 4e-46 | 10.7 EB05 7.1 · IC025 +2.5 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=20 | not reported in cached trials |
| Economic problem | 114 | 11.5 9.6–13.8ROR 11.6 · χ² 1,078 / p 1e-236 | 11.3 EB05 9.6 · IC025 +3.1 3/3 methods agree | Reporting / coding artifact | serious PRR 10.9 · 77% consumer | not reported in cached trials |
| Bronchitis chronic | 17 | 10.8 6.7–17.3ROR 10.8 · χ² 140 / p 1e-32 | 9.5 EB05 5.9 · IC025 +2.3 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=16 | not reported in cached trials |
| Diabetic neuropathy | 33 | 10.3 7.3–14.5ROR 10.3 · χ² 267 / p 3e-60 | 9.7 EB05 7.0 · IC025 +2.6 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=33 | not reported in cached trials |
| Femoral neck fracture | 34 | 10.3 7.4–14.4ROR 10.3 · χ² 275 / p 5e-62 | 9.7 EB05 7.1 · IC025 +2.6 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=34 · 100% clinician | not reported in cached trials |
| Rhinitis allergic | 29 | 10.2 7.1–14.6ROR 10.2 · χ² 229 / p 5e-52 | 9.4 EB05 6.7 · IC025 +2.5 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=27 | not reported in cached trials |
| Lumbar spinal stenosis | 19 | 10.1 6.4–15.8ROR 10.1 · χ² 146 / p 8e-34 | 8.9 EB05 5.8 · IC025 +2.3 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=18 | not reported in cached trials |
| Multiple injuries | 41 | 10.0 7.4–13.6ROR 10.0 · χ² 321 / p 4e-72 | 9.5 EB05 7.1 · IC025 +2.6 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=41 | not reported in cached trials |
| Acute sinusitis | 11 | 9.9 5.5–18.0ROR 10.0 · χ² 79 / p 3e-19 | 8.0 EB05 4.4 · IC025 +1.8 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=10 | not reported in cached trials |
| Hypertensive heart disease | 12 | 9.9 5.6–17.5ROR 9.9 · χ² 87 / p 6e-21 | 8.1 EB05 4.6 · IC025 +1.9 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=12 | not reported in cached trials |
| Narcolepsy | 12 | 9.9 5.6–17.5ROR 9.9 · χ² 87 / p 6e-21 | 8.1 EB05 4.6 · IC025 +1.9 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=11 | not reported in cached trials |
| Wound infection staphylococcal | 11 | 9.8 5.4–17.8ROR 9.8 · χ² 78 / p 5e-19 | 7.9 EB05 4.4 · IC025 +1.8 3/3 methods agree | No label text to screen label has no adverse-reaction text | – | not reported in cached trials |
| Spondylolisthesis | 11 | 9.8 5.4–17.8ROR 9.8 · χ² 78 / p 5e-19 | 7.9 EB05 4.4 · IC025 +1.8 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=10 | not reported in cached trials |
| Left ventricular hypertrophy | 27 | 9.8 6.7–14.3ROR 9.8 · χ² 203 / p 2e-46 | 9.0 EB05 6.3 · IC025 +2.4 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=27 | not reported in cached trials |
| Diverticulum | 45 | 9.7 7.3–13.0ROR 9.7 · χ² 341 / p 2e-76 | 9.2 EB05 7.1 · IC025 +2.6 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious n=42 | not reported in cached trials |
| Hyperlipidaemia | 74 | 9.6 7.6–12.1ROR 9.7 · χ² 559 / p 8e-124 | 9.3 EB05 7.6 · IC025 +2.8 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 8.3 | not reported in cached trials |
| Renal injury | 185 | 9.6 8.3–11.1ROR 9.7 · χ² 1,408 / p <1e-300 | 9.4 EB05 8.3 · IC025 +3.0 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 8.4 | 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 Meclizine 25Mg 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).
- NCT01443858 — Meclizine as a Potential Smoking Cessation Treatment (N=146, PHASE2; 16 AE terms posted; arms: Control; 25mg Meclizine; 50mg Meclizine)
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 |
|---|---|---|---|---|---|---|
| Dizziness | 1,361 | 4.2 4.0–4.5ROR 4.6 · χ² 3,437 / p <1e-300 | 4.2 EB05 4.0 · IC025 +2.0 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 4.1 | not reported in cached trials |
| Nausea | 1,163 | 2.3 2.2–2.4ROR 2.4 · χ² 868 / p 4e-191 | 2.3 EB05 2.2 · IC025 +1.1 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 2.5 | NCT01443858: 2/25 (8.0%) on Meclizine 25Mg; 6/19 (31.6%) control |
| Fatigue (tiredness) | 1,061 | 2.1 2.0–2.2ROR 2.2 · χ² 645 / p 1e-142 | 2.1 EB05 2.0 · IC025 +1.0 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 2.2 | NCT01443858: 5/25 (20.0%) on Meclizine 25Mg; 2/19 (10.5%) control |
| Diarrhoea (diarrhea) | 851 | 2.0 1.9–2.2ROR 2.1 · χ² 469 / p 2e-104 | 2.0 EB05 1.9 · IC025 +0.9 | No label text to screen label has no adverse-reaction text | serious PRR 2.0 | NCT01443858: 1/25 (4.0%) on Meclizine 25Mg; 2/19 (10.5%) control |
| Headache | 829 | 2.0 1.9–2.2ROR 2.1 · χ² 458 / p 7e-102 | 2.0 EB05 1.9 · IC025 +0.9 | No label text to screen label has no adverse-reaction text | serious PRR 2.2 | NCT01443858: 2/25 (8.0%) on Meclizine 25Mg; 3/19 (15.8%) control |
| Fall | 823 | 3.8 3.6–4.1ROR 4.0 · χ² 1,747 / p <1e-300 | 3.8 EB05 3.6 · IC025 +1.8 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 3.5 | not reported in cached trials |
| Pain | 806 | 2.0 1.9–2.2ROR 2.1 · χ² 431 / p 4e-96 | 2.0 EB05 1.9 · IC025 +0.9 | No label text to screen label has no adverse-reaction text | serious PRR 2.1 | not reported in cached trials |
| Chronic kidney disease | 787 | 16.0 15.0–17.2ROR 17.0 · χ² 11,010 / p <1e-300 | 15.9 EB05 15.0 · IC025 +3.9 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 14.2 | not reported in cached trials |
| Dyspnoea (shortness of breath) | 714 | 2.0 1.8–2.1ROR 2.0 · χ² 341 / p 2e-76 | 2.0 EB05 1.8 · IC025 +0.8 | No label text to screen label has no adverse-reaction text | serious PRR 1.8 | not reported in cached trials |
| Asthenia (weakness) | 690 | 2.8 2.6–3.1ROR 2.9 · χ² 836 / p 5e-184 | 2.8 EB05 2.7 · IC025 +1.4 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 2.7 | not reported in cached trials |
| Vomiting | 615 | 2.0 1.9–2.2ROR 2.1 · χ² 328 / p 2e-73 | 2.0 EB05 1.9 · IC025 +0.9 | No label text to screen label has no adverse-reaction text | serious PRR 1.9 | not reported in cached trials |
| Renal failure (kidney failure) | 610 | 7.1 6.6–7.7ROR 7.4 · χ² 3,186 / p <1e-300 | 7.0 EB05 6.6 · IC025 +2.7 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 6.3 | not reported in cached trials |
| Drug ineffective (drug did not work) | 604 | 0.7 0.7–0.8ROR 0.7 · χ² 76 / p 1e-18 | 0.7 EB05 0.7 · IC025 -0.6 PRR-only: not supported by EBGM or IC | Reporting / coding artifact | serious PRR 0.7 | not reported in cached trials |
| Acute kidney injury (sudden kidney damage) | 564 | 5.7 5.3–6.2ROR 6.0 · χ² 2,215 / p <1e-300 | 5.7 EB05 5.3 · IC025 +2.4 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 5.1 | not reported in cached trials |
| Vertigo (spinning dizziness) | 523 | 13.4 12.3–14.6ROR 13.9 · χ² 5,942 / p <1e-300 | 13.3 EB05 12.3 · IC025 +3.6 3/3 methods agree | No label text to screen label has no adverse-reaction text | serious PRR 10.8 | not reported in cached trials |
Unlabeled candidate signals
Every screened signal with n ≥ 20 was either labeled, an indication term, or an artifact pattern — no unlabeled candidate stood out in the top signals.
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 Meclizine 25Mg?
In FDA FAERS, the most frequently co-reported reaction terms for Meclizine 25Mg are dizziness, nausea, fatigue, diarrhoea, headache, fall. 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 Meclizine 25Mg have an FDA boxed warning?
No. The FDA label retrieved for Meclizine 25Mg has no boxed warning; see the label's Warnings and Precautions for the recognised risks.
Do FAERS signals prove that Meclizine 25Mg 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 cf79ac74-017e-4fb4-85d3-4ea944080e89, effective 20250306; matched on
openfda.generic_name.exact:"MECLIZINE HCL 25MG") - 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, 1,146 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
MECLIZINE 25MG, 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.