Drug · FAERS side-effect profile with label screen

Hydroxyzine Hydrochloride side effects: what 13,055 FDA adverse event reports show

Hydroxyzine Hydrochloride · Hydroxyzine Hydrochloride · 1,113 reaction terms · 56,428 drug–reaction co-reports · data 2026-09-14

Drug class

Not stated in label

Brand names

Hydroxyzine Hydrochloride

openFDA label

Who reports

13,055 reports · 55% serious · 1,324 with death outcome · 69% female

openFDA FAERS counts, all years, deduplication not applied

Used for

For symptomatic relief of anxiety and tension associated with psychoneurosis and as an adjunct in organic disease states in which anxiety is manifested. Useful in the management of pruritus due to allergic conditions such as chronic urticaria and atopic and contact dermatoses and in histamine-mediated pruritus.

FDA label, Indications and Usage

What it is

DESCRIPTION Hydroxyzine hydrochloride, USP has the chemical name of 2-[2-[4-(p-Chloro-α-phenylbenzyl)-1-piperazinyl]ethoxy] ethanol dihydrochloride. C 21 H 27 ClN 2 0 2 •2HCI M.W. 447.83 Hydroxyzine hydrochloride, USP occurs as a white, odorless powder which is very soluble in water.

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) 1Likely indication confounding 2Reporting / coding artifact 7Not in label — unassessed 30

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.
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. 1,073 further terms are in the interactive explorer. Reaction links open the term's cross-drug page.

Show: hide coding/lab/outcome terms hide indication terms unlabeled only hide PRR-only

Reaction	Reports	PRR 95% CI · ROR · χ²/p	EBGM EB05 · IC025	Label screen	Serious-only & strata	Trial cross-check
Neuroglycopenia	10	163.1 85.1–312.6ROR 163.2 · χ² 1,317 / p 1e-288	115.8 EB05 67.2 · IC025 +3.1 3/3 methods agree	Not in label — unassessed	serious n=10	no trial arm names this drug
Neuroblastoma recurrent	16	138.3 83.0–230.4ROR 138.5 · χ² 1,881 / p <1e-300	110.8 EB05 72.3 · IC025 +3.9 3/3 methods agree	Not in label — unassessed	serious n=16	no trial arm names this drug
Chemical submission	12	81.8 45.8–146.1ROR 81.9 · χ² 835 / p 5e-184	69.6 EB05 42.4 · IC025 +3.3 3/3 methods agree	Not in label — unassessed	serious n=12	no trial arm names this drug
Vascular access site complication	11	75.3 41.1–137.9ROR 75.4 · χ² 701 / p 1e-154	64.3 EB05 38.3 · IC025 +3.1 3/3 methods agree	Reporting / coding artifact	–	no trial arm names this drug
Infusion site discharge	54	52.3 39.9–68.5ROR 52.5 · χ² 2,579 / p <1e-300	49.8 EB05 39.6 · IC025 +4.7 3/3 methods agree	Not in label — unassessed	serious n=38 · ♀ 91% (drug 69%) · 89% consumer	no trial arm names this drug
Peripheral circulatory failure	12	48.4 27.3–86.0ROR 48.5 · χ² 496 / p 4e-110	44.0 EB05 26.8 · IC025 +3.1 3/3 methods agree	Not in label — unassessed	serious n=12	no trial arm names this drug
Device maintenance issue	14	40.8 24.0–69.3ROR 40.8 · χ² 492 / p 3e-109	37.9 EB05 24.0 · IC025 +3.2 3/3 methods agree	Reporting / coding artifact	serious n=8	no trial arm names this drug
Victim of chemical submission	14	39.2 23.1–66.6ROR 39.2 · χ² 472 / p 6e-105	36.5 EB05 23.1 · IC025 +3.2 3/3 methods agree	Not in label — unassessed	serious n=14	no trial arm names this drug
Multiple drug therapy	15	35.2 21.1–58.7ROR 35.2 · χ² 455 / p 3e-101	33.1 EB05 21.3 · IC025 +3.2 3/3 methods agree	Reporting / coding artifact	serious n=15	no trial arm names this drug
Victim of crime	25	34.6 23.3–51.4ROR 34.6 · χ² 765 / p 1e-168	33.1 EB05 23.6 · IC025 +3.7 3/3 methods agree	Not in label — unassessed	serious n=25 · 100% clinician	no trial arm names this drug
Bacterial disease carrier	15	33.7 20.2–56.2ROR 33.7 · χ² 435 / p 8e-97	31.8 EB05 20.5 · IC025 +3.2 3/3 methods agree	Reporting / coding artifact	serious n=15	no trial arm names this drug
Pigmentary maculopathy	10	33.5 17.9–62.7ROR 33.5 · χ² 278 / p 1e-62	31.0 EB05 17.9 · IC025 +2.6 3/3 methods agree	Not in label — unassessed	serious n=10	no trial arm names this drug
Bronchial wall thickening	13	29.2 16.9–50.6ROR 29.3 · χ² 321 / p 4e-72	27.7 EB05 17.1 · IC025 +2.9 3/3 methods agree	Not in label — unassessed	serious n=13	no trial arm names this drug
Sleep disorder due to a general medical condition	238	23.9 21.1–27.2ROR 24.4 · χ² 5,136 / p <1e-300	23.6 EB05 21.2 · IC025 +4.3 3/3 methods agree	Not in label — unassessed	serious PRR 3.9	no trial arm names this drug
Product name confusion	16	23.7 14.5–38.9ROR 23.8 · χ² 321 / p 4e-72	22.8 EB05 14.8 · IC025 +3.0 3/3 methods agree	Reporting / coding artifact	–	no trial arm names this drug
Mast cell activation syndrome	19	23.3 14.8–36.7ROR 23.4 · χ² 379 / p 1e-84	22.5 EB05 15.2 · IC025 +3.1 3/3 methods agree	Not in label — unassessed	serious n=19	no trial arm names this drug
Infusion site haemorrhage	44	22.1 16.4–29.7ROR 22.1 · χ² 852 / p 1e-187	21.6 EB05 16.7 · IC025 +3.6 3/3 methods agree	Not in label — unassessed	serious n=31 · ♀ 91% (drug 69%) · 77% consumer	no trial arm names this drug
Infusion site pruritus	39	20.3 14.8–27.8ROR 20.4 · χ² 688 / p 7e-152	19.9 EB05 15.1 · IC025 +3.5 3/3 methods agree	Likely indication confounding term in indications; also in warnings	serious n=27	no trial arm names this drug
Periorbital pain	10	20.2 10.8–37.7ROR 20.2 · χ² 162 / p 2e-37	18.8 EB05 10.0 · IC025 +2.3 3/3 methods agree	Not in label — unassessed	–	no trial arm names this drug
Infusion site warmth	14	18.9 11.1–32.0ROR 18.9 · χ² 217 / p 2e-49	17.9 EB05 10.9 · IC025 +2.6 3/3 methods agree	Not in label — unassessed	serious n=8	no trial arm names this drug
Device infusion issue	28	18.5 12.8–26.9ROR 18.6 · χ² 442 / p 2e-98	18.1 EB05 13.0 · IC025 +3.2 3/3 methods agree	Reporting / coding artifact	serious n=20 · ♀ 89% (drug 69%) · 100% consumer	no trial arm names this drug
Infusion site mass	12	18.2 10.3–32.2ROR 18.2 · χ² 176 / p 2e-40	17.0 EB05 9.6 · IC025 +2.4 3/3 methods agree	Not in label — unassessed	serious n=10	no trial arm names this drug
Product administration interrupted	82	17.3 13.9–21.5ROR 17.4 · χ² 1,232 / p 4e-270	17.1 EB05 14.2 · IC025 +3.6 3/3 methods agree	Reporting / coding artifact	serious n=77	no trial arm names this drug
Infusion site irritation	13	16.9 9.8–29.2ROR 17.0 · χ² 177 / p 9e-41	15.8 EB05 9.1 · IC025 +2.5 3/3 methods agree	Not in label — unassessed	serious n=7	no trial arm names this drug
Bronchial secretion retention	13	16.6 9.6–28.7ROR 16.7 · χ² 174 / p 5e-40	15.5 EB05 8.9 · IC025 +2.5 3/3 methods agree	Not in label — unassessed	serious n=13	no trial arm names this drug
Dermatitis atopic	513	16.6 15.3–18.1ROR 17.3 · χ² 7,460 / p <1e-300	16.5 EB05 15.3 · IC025 +3.9 3/3 methods agree	Not in label — unassessed	serious n=39	no trial arm names this drug
Drowning	10	16.1 8.6–30.1ROR 16.1 · χ² 126 / p 2e-29	14.4 EB05 7.2 · IC025 +2.1 3/3 methods agree	Not in label — unassessed	serious n=10	no trial arm names this drug
Infusion site induration	14	15.9 9.4–27.0ROR 16.0 · χ² 180 / p 3e-41	14.9 EB05 8.7 · IC025 +2.5 3/3 methods agree	Not in label — unassessed	serious n=9	no trial arm names this drug
Neurodermatitis	34	15.8 11.3–22.1ROR 15.8 · χ² 452 / p 1e-100	15.4 EB05 11.4 · IC025 +3.1 3/3 methods agree	Not in label — unassessed	serious n=7	no trial arm names this drug
Infusion site infection	22	15.7 10.3–23.9ROR 15.7 · χ² 286 / p 2e-64	15.1 EB05 10.2 · IC025 +2.8 3/3 methods agree	Not in label — unassessed	serious n=15	no trial arm names this drug
Infusion site bruising	20	15.2 9.8–23.6ROR 15.2 · χ² 249 / p 2e-56	14.5 EB05 9.5 · IC025 +2.7 3/3 methods agree	Not in label — unassessed	serious n=17	no trial arm names this drug
Postural orthostatic tachycardia syndrome	12	14.8 8.4–26.1ROR 14.8 · χ² 140 / p 2e-32	13.4 EB05 7.2 · IC025 +2.3 3/3 methods agree	Not in label — unassessed	serious n=11	no trial arm names this drug
Infusion site pain	116	14.7 12.2–17.6ROR 14.8 · χ² 1,454 / p <1e-300	14.5 EB05 12.4 · IC025 +3.5 3/3 methods agree	Not in label — unassessed	serious n=77 · 83% consumer	no trial arm names this drug
Infusion site erythema	70	13.6 10.8–17.3ROR 13.7 · χ² 801 / p 1e-176	13.4 EB05 10.9 · IC025 +3.2 3/3 methods agree	Not in label — unassessed	serious n=43 · ♀ 90% (drug 69%) · 91% consumer	no trial arm names this drug
Skin discomfort	22	13.4 8.8–20.3ROR 13.4 · χ² 238 / p 6e-54	12.6 EB05 8.4 · IC025 +2.7 3/3 methods agree	Not in label — unassessed	–	no trial arm names this drug
Eyelid pain	16	13.3 8.1–21.8ROR 13.3 · χ² 169 / p 6e-39	12.2 EB05 7.3 · IC025 +2.4 3/3 methods agree	Not in label — unassessed	–	no trial arm names this drug
Obstructive sleep apnoea syndrome	11	12.7 7.0–23.0ROR 12.7 · χ² 107 / p 3e-25	10.9 EB05 5.7 · IC025 +2.0 3/3 methods agree	Not in label — unassessed	serious n=10	no trial arm names this drug
Distributive shock	17	12.4 7.7–20.0ROR 12.4 · χ² 166 / p 3e-38	11.3 EB05 6.9 · IC025 +2.4 3/3 methods agree	Not in label — unassessed	serious n=17	no trial arm names this drug
Dermatitis contact	87	12.4 10.0–15.3ROR 12.5 · χ² 892 / p 3e-196	12.1 EB05 10.1 · IC025 +3.2 3/3 methods agree	Likely indication confounding shares a disease stem with the indications wording	serious n=52 · 80% consumer	no trial arm names this drug
Anticholinergic syndrome	12	12.2 6.9–21.5ROR 12.2 · χ² 111 / p 3e-26	10.4 EB05 5.7 · IC025 +2.1 3/3 methods agree	Labeled (related wording) related wording	serious n=12	no trial arm names this drug

Trial evidence (ClinicalTrials.gov)

ClinicalTrials.gov returned results-bearing trials mentioning Hydroxyzine only as a background or rescue medication (NCT01916226, NCT00291642); no trial listing it as the tested intervention was cached, so no trial cross-check is shown.

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
Pruritus (itching)	1,094	4.7 4.4–4.9ROR 5.0 · χ² 3,182 / p <1e-300	4.6 EB05 4.4 · IC025 +2.1 3/3 methods agree	Likely indication confounding term in indications; also in warnings	serious PRR 4.1	no trial arm names this drug
Drug ineffective (drug did not work)	969	1.2 1.1–1.3ROR 1.2 · χ² 28 / p 5e-8	1.2 EB05 1.1 · IC025 +0.1	Reporting / coding artifact	serious PRR 1.3	no trial arm names this drug
Nausea	830	1.7 1.6–1.8ROR 1.7 · χ² 241 / p 1e-54	1.7 EB05 1.6 · IC025 +0.6	Not in label — unassessed	serious PRR 2.2	no trial arm names this drug
Fatigue (tiredness)	825	1.7 1.6–1.8ROR 1.8 · χ² 248 / p 3e-56	1.7 EB05 1.6 · IC025 +0.7	Not in label — unassessed	serious PRR 2.0	no trial arm names this drug
Rash	799	3.0 2.8–3.2ROR 3.1 · χ² 1,054 / p 2e-231	3.0 EB05 2.8 · IC025 +1.4 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 2.2	no trial arm names this drug
Product dose omission issue	788	4.4 4.2–4.8ROR 4.7 · χ² 2,126 / p <1e-300	4.4 EB05 4.2 · IC025 +2.0 3/3 methods agree	Reporting / coding artifact	serious PRR 7.7	no trial arm names this drug
Headache	778	2.0 1.9–2.1ROR 2.1 · χ² 396 / p 2e-88	2.0 EB05 1.9 · IC025 +0.9	Labeled adverse reaction exact term	serious PRR 2.5	no trial arm names this drug
Pain	704	1.8 1.7–2.0ROR 1.9 · χ² 275 / p 5e-62	1.8 EB05 1.7 · IC025 +0.8	Not in label — unassessed	serious PRR 1.9	no trial arm names this drug
Off label use (used outside approved label)	667	1.2 1.1–1.3ROR 1.2 · χ² 30 / p 2e-8	1.2 EB05 1.2 · IC025 +0.2	Reporting / coding artifact	serious PRR 1.5	no trial arm names this drug
Toxicity to various agents	635	6.1 5.6–6.6ROR 6.3 · χ² 2,706 / p <1e-300	6.0 EB05 5.7 · IC025 +2.5 3/3 methods agree	Not in label — unassessed	serious PRR 6.6 · 97% clinician	no trial arm names this drug
Diarrhoea (diarrhea)	603	1.5 1.4–1.6ROR 1.5 · χ² 104 / p 8e-25	1.5 EB05 1.4 · IC025 +0.5	Not in label — unassessed	serious PRR 1.7	no trial arm names this drug
Dyspnoea (shortness of breath)	574	1.6 1.5–1.8ROR 1.7 · χ² 142 / p 4e-33	1.6 EB05 1.5 · IC025 +0.6	Not in label — unassessed	serious PRR 1.8	no trial arm names this drug
Vomiting	530	1.8 1.7–2.0ROR 1.8 · χ² 197 / p 5e-45	1.8 EB05 1.7 · IC025 +0.7	Not in label — unassessed	serious PRR 2.1	no trial arm names this drug
Dermatitis atopic	513	16.6 15.3–18.1ROR 17.3 · χ² 7,460 / p <1e-300	16.5 EB05 15.3 · IC025 +3.9 3/3 methods agree	Not in label — unassessed	serious n=39	no trial arm names this drug
Dizziness	479	1.5 1.4–1.7ROR 1.6 · χ² 93 / p 2e-22	1.5 EB05 1.4 · IC025 +0.5	Not in label — unassessed	serious PRR 1.9	no trial arm names this drug

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.

Infusion site discharge — n=54, PRR 52.3
Victim of crime — n=25, PRR 34.6
Sleep disorder due to a general medical condition — n=238, PRR 23.9
Infusion site haemorrhage — n=44, PRR 22.1
Dermatitis atopic — n=513, PRR 16.6
Neurodermatitis — n=34, PRR 15.8
Infusion site infection — n=22, PRR 15.7
Infusion site bruising — n=20, PRR 15.2
Infusion site pain — n=116, PRR 14.7
Infusion site erythema — n=70, PRR 13.6

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 Hydroxyzine?

In FDA FAERS, the most frequently co-reported reaction terms for Hydroxyzine are pruritus, nausea, fatigue, rash, headache, pain. 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 Hydroxyzine have an FDA boxed warning?

No. The FDA label retrieved for Hydroxyzine has no boxed warning; see the label's Warnings and Precautions for the recognised risks.

Do FAERS signals prove that Hydroxyzine 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 89901966-724b-4773-98b8-ea663ceabd53, effective 20241025; matched on openfda.generic_name.exact:"HYDROXYZINE")
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, field patient.drug.openfda.generic_name.exact, 1,113 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 HYDROXYZINE, 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.