Azelastine side effects: what 17,830 FDA adverse event reports show

Azelastine · Azelastine Hydrochloride · 1,115 reaction terms · 67,561 drug–reaction co-reports · data 2026-09-14

Drug class

H 1 -receptor antagonist

FDA label, Indications wording

Brand names

Azelastine Hydrochloride

openFDA label

Who reports

17,830 reports · 40% serious · 555 with death outcome · 68% female

openFDA FAERS counts, all years, deduplication not applied

Used for

Azelastine hydrochloride (HCl) nasal spray, 0.1% is indicated for the treatment of the symptoms of seasonal allergic rhinitis in adults and pediatric patients 5 years and older, and for the treatment of the symptoms of vasomotor rhinitis in adults and adolescent patients 12 years and older.

FDA label, Indications and Usage

What it is

Azelastine HCl nasal spray, 0.1%, 137 micrograms (mcg), is an antihistamine formulated as a metered-spray solution for intranasal administration. Azelastine HCl, USP occurs as a white, almost odorless, crystalline powder with a bitter taste. It has a molecular weight of 418.37.

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) 6Likely indication confounding 3Reporting / coding artifact 5Not 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.
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. 1,075 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
Product delivery mechanism issue	337	87.4 78.3–97.6ROR 89.1 · χ² 26,697 / p <1e-300	81.0 EB05 74.0 · IC025 +6.0 3/3 methods agree	Reporting / coding artifact	81% consumer	not reported in cached trials
Prolonged expiration	14	65.6 38.3–112.4ROR 65.7 · χ² 783 / p 1e-172	57.5 EB05 36.4 · IC025 +3.4 3/3 methods agree	Not in label — unassessed	serious n=14	not reported in cached trials
Infusion site discharge	55	39.0 29.8–51.0ROR 39.1 · χ² 1,933 / p <1e-300	37.3 EB05 29.7 · IC025 +4.4 3/3 methods agree	Not in label — unassessed	serious n=48 · 80% consumer	not reported in cached trials
Nasal turbinate hypertrophy	11	35.4 19.4–64.4ROR 35.4 · χ² 324 / p 1e-72	32.6 EB05 19.4 · IC025 +2.8 3/3 methods agree	Not in label — unassessed	serious n=9	not reported in cached trials
Temporomandibular pain and dysfunction syndrome	10	30.6 16.3–57.4ROR 30.6 · χ² 251 / p 7e-57	28.3 EB05 16.3 · IC025 +2.6 3/3 methods agree	Not in label — unassessed	serious n=9	not reported in cached trials
Infusion site bruising	52	29.4 22.3–38.7ROR 29.5 · χ² 1,364 / p 6e-299	28.4 EB05 22.5 · IC025 +4.0 3/3 methods agree	Not in label — unassessed	serious n=41	not reported in cached trials
Precancerous condition	16	29.4 17.9–48.3ROR 29.4 · χ² 401 / p 2e-89	27.8 EB05 18.1 · IC025 +3.1 3/3 methods agree	Not in label — unassessed	serious n=16	not reported in cached trials
Treatment failure	1,878	27.5 26.3–28.7ROR 30.6 · χ² 46,968 / p <1e-300	26.9 EB05 25.9 · IC025 +4.7 3/3 methods agree	Reporting / coding artifact	80% consumer	not reported in cached trials
Sputum purulent	15	27.2 16.3–45.3ROR 27.2 · χ² 344 / p 3e-77	25.8 EB05 16.5 · IC025 +3.0 3/3 methods agree	Not in label — unassessed	serious n=15	not reported in cached trials
Infusion site mass	24	27.0 18.0–40.4ROR 27.0 · χ² 562 / p 2e-124	25.9 EB05 18.3 · IC025 +3.4 3/3 methods agree	Not in label — unassessed	serious n=20 · ♀ 100% (drug 68%)	not reported in cached trials
Infusion site haemorrhage	69	25.5 20.1–32.4ROR 25.6 · χ² 1,567 / p <1e-300	24.8 EB05 20.3 · IC025 +4.0 3/3 methods agree	Not in label — unassessed	serious n=48 · 77% consumer	not reported in cached trials
Infusion site urticaria	14	25.5 15.0–43.3ROR 25.5 · χ² 299 / p 3e-67	24.2 EB05 15.2 · IC025 +2.9 3/3 methods agree	Not in label — unassessed	serious n=10	not reported in cached trials
Infusion site pruritus	57	21.9 16.8–28.4ROR 21.9 · χ² 1,093 / p 6e-240	21.3 EB05 17.1 · IC025 +3.7 3/3 methods agree	Labeled (related wording) related wording	serious n=35	not reported in cached trials
Infusion site discomfort	17	19.8 12.3–32.0ROR 19.9 · χ² 281 / p 3e-63	19.0 EB05 12.3 · IC025 +2.9 3/3 methods agree	Not in label — unassessed	serious n=10	not reported in cached trials
Infusion site swelling	95	18.4 15.0–22.5ROR 18.5 · χ² 1,521 / p <1e-300	18.1 EB05 15.2 · IC025 +3.7 3/3 methods agree	Not in label — unassessed	serious n=58	not reported in cached trials
Endocrine ophthalmopathy	12	17.3 9.8–30.6ROR 17.3 · χ² 166 / p 3e-38	16.0 EB05 8.9 · IC025 +2.4 3/3 methods agree	Not in label — unassessed	serious n=12	not reported in cached trials
Allergic sinusitis	12	16.6 9.4–29.3ROR 16.6 · χ² 158 / p 1e-36	15.3 EB05 8.4 · IC025 +2.4 3/3 methods agree	Labeled (related wording) related wording	serious n=9	not reported in cached trials
Chronic kidney disease-mineral and bone disorder	15	16.6 10.0–27.6ROR 16.6 · χ² 202 / p 5e-46	15.6 EB05 9.4 · IC025 +2.6 3/3 methods agree	Not in label — unassessed	serious n=15	not reported in cached trials
Multiple allergies	109	16.5 13.7–20.0ROR 16.6 · χ² 1,553 / p <1e-300	16.3 EB05 13.8 · IC025 +3.6 3/3 methods agree	Likely indication confounding shares a disease stem with the indications wording	serious n=86 · 72% consumer	not reported in cached trials
Infusion site rash	18	15.7 9.9–25.0ROR 15.7 · χ² 230 / p 3e-52	14.9 EB05 9.5 · IC025 +2.7 3/3 methods agree	Labeled (related wording) related wording	serious n=12	not reported in cached trials
Bone demineralisation	14	15.7 9.3–26.6ROR 15.7 · χ² 176 / p 2e-40	14.5 EB05 8.5 · IC025 +2.5 3/3 methods agree	Not in label — unassessed	serious n=13	not reported in cached trials
Obstructive sleep apnoea syndrome	18	15.3 9.6–24.4ROR 15.3 · χ² 224 / p 6e-51	14.5 EB05 9.2 · IC025 +2.7 3/3 methods agree	Not in label — unassessed	serious n=17	not reported in cached trials
Infusion site discolouration	11	15.2 8.4–27.5ROR 15.2 · χ² 130 / p 2e-30	13.5 EB05 7.0 · IC025 +2.2 3/3 methods agree	Not in label — unassessed	serious n=7	not reported in cached trials
Seasonal allergy	179	15.1 13.0–17.5ROR 15.2 · χ² 2,309 / p <1e-300	14.9 EB05 13.1 · IC025 +3.6 3/3 methods agree	Likely indication confounding shares a disease stem with the indications wording	serious n=114 · 76% consumer	not reported in cached trials
Infusion site erythema	104	14.9 12.3–18.1ROR 15.0 · χ² 1,319 / p 4e-289	14.7 EB05 12.4 · IC025 +3.5 3/3 methods agree	Not in label — unassessed	serious n=67	not reported in cached trials
Periorbital pain	10	14.8 7.9–27.6ROR 14.8 · χ² 114 / p 7e-27	12.9 EB05 6.4 · IC025 +2.1 3/3 methods agree	Not in label — unassessed	–	not reported in cached trials
Chronic sinusitis	46	14.6 10.9–19.5ROR 14.6 · χ² 562 / p 2e-124	14.2 EB05 11.0 · IC025 +3.2 3/3 methods agree	Labeled (related wording) related wording	serious n=37	not reported in cached trials
Infusion site nodule	11	14.5 8.0–26.3ROR 14.5 · χ² 124 / p 5e-29	12.8 EB05 6.6 · IC025 +2.2 3/3 methods agree	Not in label — unassessed	–	not reported in cached trials
Postural orthostatic tachycardia syndrome	16	14.5 8.9–23.7ROR 14.5 · χ² 185 / p 2e-42	13.5 EB05 8.1 · IC025 +2.5 3/3 methods agree	Not in label — unassessed	serious n=13	not reported in cached trials
Mycotic allergy	10	14.1 7.6–26.3ROR 14.1 · χ² 108 / p 2e-25	12.1 EB05 6.0 · IC025 +2.0 3/3 methods agree	Likely indication confounding shares a disease stem with the indications wording	serious n=8	not reported in cached trials
Nasal septum deviation	23	14.0 9.3–21.0ROR 14.0 · χ² 261 / p 6e-59	13.3 EB05 8.9 · IC025 +2.7 3/3 methods agree	Not in label — unassessed	serious n=16	not reported in cached trials
Sinusitis bacterial	12	13.4 7.6–23.7ROR 13.4 · χ² 125 / p 3e-29	11.8 EB05 6.4 · IC025 +2.2 3/3 methods agree	Not in label — unassessed	serious n=11	not reported in cached trials
Infusion site irritation	14	13.4 7.9–22.6ROR 13.4 · χ² 146 / p 6e-34	12.0 EB05 6.9 · IC025 +2.3 3/3 methods agree	Labeled (related wording) related wording	serious n=11	not reported in cached trials
Product leakage	60	13.4 10.4–17.2ROR 13.4 · χ² 666 / p 4e-147	13.0 EB05 10.4 · IC025 +3.2 3/3 methods agree	Reporting / coding artifact	85% consumer	not reported in cached trials
Upper-airway cough syndrome	92	13.3 10.9–16.4ROR 13.4 · χ² 1,025 / p 3e-225	13.1 EB05 10.9 · IC025 +3.3 3/3 methods agree	Not in label — unassessed	serious n=41	not reported in cached trials
Device infusion issue	27	13.1 8.9–19.1ROR 13.1 · χ² 286 / p 2e-64	12.4 EB05 8.7 · IC025 +2.8 3/3 methods agree	Reporting / coding artifact	serious n=19 · ♀ 89% (drug 68%) · 85% consumer	not reported in cached trials
Sinus operation	26	13.0 8.8–19.1ROR 13.0 · χ² 272 / p 2e-61	12.3 EB05 8.5 · IC025 +2.7 3/3 methods agree	Reporting / coding artifact	serious n=17	not reported in cached trials
Infusion site warmth	13	12.8 7.4–22.1ROR 12.8 · χ² 129 / p 4e-30	11.3 EB05 6.3 · IC025 +2.2 3/3 methods agree	Not in label — unassessed	serious n=10	not reported in cached trials
Impaired quality of life	154	12.7 10.8–14.9ROR 12.8 · χ² 1,630 / p <1e-300	12.5 EB05 10.9 · IC025 +3.3 3/3 methods agree	Not in label — unassessed	serious PRR 7.7	not reported in cached trials
Nasal pruritus	13	12.4 7.2–21.4ROR 12.4 · χ² 124 / p 4e-29	10.8 EB05 6.1 · IC025 +2.2 3/3 methods agree	Labeled (related wording) related wording	–	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 Azelastine 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).

NCT00883168 — A Study to Evaluate the Safety and Effectiveness of a Nasal Spray to Treat Seasonal Allergies (N=1791, PHASE3; 10 AE terms posted; arms: MP29-02; Azelastine Hcl; Fluticasone Propionate; 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
Treatment failure	1,878	27.5 26.3–28.7ROR 30.6 · χ² 46,968 / p <1e-300	26.9 EB05 25.9 · IC025 +4.7 3/3 methods agree	Reporting / coding artifact	80% consumer	not reported in cached trials
Fatigue (tiredness)	1,247	1.9 1.8–2.0ROR 2.0 · χ² 538 / p 3e-119	1.9 EB05 1.8 · IC025 +0.8	Labeled adverse reaction exact term	serious PRR 2.8	not reported in cached trials
Drug ineffective (drug did not work)	1,238	1.1 1.0–1.2ROR 1.1 · χ² 13 / p 2e-4	1.1 EB05 1.1 · IC025 +0.0	Reporting / coding artifact	serious PRR 0.9	not reported in cached trials
Product dose omission issue	984	4.1 3.8–4.3ROR 4.2 · χ² 2,298 / p <1e-300	4.1 EB05 3.8 · IC025 +1.9 3/3 methods agree	Reporting / coding artifact	serious PRR 8.7 · 71% consumer	not reported in cached trials
Headache	962	1.8 1.7–1.9ROR 1.9 · χ² 355 / p 2e-79	1.8 EB05 1.7 · IC025 +0.7	Labeled adverse reaction exact term	serious PRR 2.7	NCT00883168: 14/449 (3.1%) on Azelastine; 4/451 (0.9%) control
Nausea	951	1.4 1.3–1.5ROR 1.4 · χ² 120 / p 3e-28	1.4 EB05 1.3 · IC025 +0.4	Labeled adverse reaction exact term	serious PRR 2.3	not reported in cached trials
Dyspnoea (shortness of breath)	927	1.9 1.8–2.1ROR 2.0 · χ² 423 / p 3e-94	1.9 EB05 1.8 · IC025 +0.8	Labeled adverse reaction exact term	serious PRR 2.3	not reported in cached trials
Diarrhoea (diarrhea)	828	1.5 1.4–1.6ROR 1.5 · χ² 148 / p 3e-34	1.5 EB05 1.4 · IC025 +0.5	Labeled adverse reaction exact term	serious PRR 2.2	not reported in cached trials
Pain	817	1.6 1.5–1.7ROR 1.6 · χ² 168 / p 8e-39	1.6 EB05 1.5 · IC025 +0.5	Labeled adverse reaction exact term	serious PRR 2.2	NCT00883168: 2/449 (0.4%) on Azelastine; 2/451 (0.4%) control
Cough	802	3.4 3.2–3.6ROR 3.5 · χ² 1,351 / p 6e-296	3.4 EB05 3.2 · IC025 +1.6 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 4.3	not reported in cached trials
Sinusitis	723	8.3 7.7–8.9ROR 8.6 · χ² 4,633 / p <1e-300	8.2 EB05 7.7 · IC025 +2.9 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 13.2	not reported in cached trials
Dizziness	681	1.6 1.5–1.7ROR 1.6 · χ² 159 / p 9e-37	1.6 EB05 1.5 · IC025 +0.6	Labeled adverse reaction exact term	serious PRR 2.3	not reported in cached trials
Asthma	587	6.2 5.7–6.7ROR 6.4 · χ² 2,542 / p <1e-300	6.1 EB05 5.7 · IC025 +2.5 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 6.1	not reported in cached trials
Pneumonia (lung infection)	582	2.1 2.0–2.3ROR 2.2 · χ² 346 / p 1e-77	2.1 EB05 2.0 · IC025 +0.9	Labeled (related wording) related wording	serious PRR 3.1	not reported in cached trials
Off label use (used outside approved label)	580	0.8 0.7–0.9ROR 0.8 · χ² 36 / p 1e-9	0.8 EB05 0.7 · IC025 -0.5 PRR-only: not supported by EBGM or IC	Reporting / coding artifact	serious PRR 1.0	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.

Infusion site discharge — n=55, PRR 39.0
Infusion site bruising — n=52, PRR 29.4
Infusion site mass — n=24, PRR 27.0
Infusion site haemorrhage — n=69, PRR 25.5
Infusion site swelling — n=95, PRR 18.4
Infusion site erythema — n=104, PRR 14.9
Nasal septum deviation — n=23, PRR 14.0
Upper-airway cough syndrome — n=92, PRR 13.3
Impaired quality of life — n=154, PRR 12.7

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 Azelastine?

In FDA FAERS, the most frequently co-reported reaction terms for Azelastine are fatigue, headache, nausea, dyspnoea, diarrhoea, 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 Azelastine have an FDA boxed warning?

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

Do FAERS signals prove that Azelastine 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 7902605c-944a-4d7e-a7d4-eb4a71bcacdb, effective 20181018; matched on openfda.generic_name.exact:"AZELASTINE")
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, 1,115 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 AZELASTINE, 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.