Apixaban side effects: what 66,516 FDA adverse event reports show

Apixaban · 1,254 reaction terms · 217,537 drug–reaction co-reports · data 2026-09-14

Drug class

Factor Xa Inhibitor

FDA label (Established Pharmacologic Class)

Who reports

66,516 reports · 96% serious · 7,220 with death outcome · 47% female

openFDA FAERS counts, all years, deduplication not applied

Used for

Apixaban is a factor Xa inhibitor indicated: to reduce the risk of stroke and systemic embolism in patients with nonvalvular atrial fibrillation. ( 1.1 ) for the prophylaxis of deep vein thrombosis (DVT), which may lead to pulmonary embolism (PE), in patients who have undergone hip or knee replacement surgery.

FDA label, Indications and Usage

What it is

Apixaban, a factor Xa (FXa) inhibitor, is chemically described as 1-(4- methoxyphenyl)-7-oxo-6-[4-(2-oxopiperidin-1-yl)phenyl]-4,5,6,7-tetrahydro-1H-pyrazolo[3,4 c]pyridine-3-carboxamide.

FDA label, Description section

Boxed warning

WARNING: (A) PREMATURE DISCONTINUATION OF APIXABAN INCREASES THE RISK OF THROMBOTIC EVENTS (B) SPINAL/EPIDURAL HEMATOMA (A) PREMATURE DISCONTINUATION OF APIXABAN INCREASES THE RISK OF THROMBOTIC EVENTS Premature discontinuation of any oral anticoagulant, including apixaban, increases the risk of thrombotic events.

FDA 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) 3Lab value / disease marker 6Not in label — unassessed 31

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.
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). 1,214 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
Cardiospasm	397	799.3 663.7–962.6ROR 804.1 · calibrated p 5e-16 ✓	221.7 EB05 204.0 · IC025 +7.3 3/3 methods agree	Not in label — unassessed	serious n=397	no trial arm names this drug
Right atrial hypertrophy	75	664.4 444.9–992.3ROR 665.2 · calibrated p 3e-14 ✓	201.3 EB05 165.9 · IC025 +6.1 3/3 methods agree	Not in label — unassessed	serious n=75 · ♀ 0% (drug 47%)	no trial arm names this drug
Immunisation	262	489.4 403.0–594.3ROR 491.3 · calibrated p 1e-13 ✓	187.8 EB05 169.5 · IC025 +6.9 3/3 methods agree	Not in label — unassessed	serious n=262	no trial arm names this drug
Palmoplantar keratoderma	389	374.6 323.2–434.1ROR 376.8 · calibrated p 1e-12 ✓	168.8 EB05 155.2 · IC025 +7.0 3/3 methods agree	Not in label — unassessed	serious n=388	no trial arm names this drug
Ejection fraction	216	185.5 156.8–219.6ROR 186.1 · calibrated p 9e-10 ✓	115.3 EB05 102.9 · IC025 +6.3 3/3 methods agree	Not in label — unassessed	serious n=216 · ♀ 100% (drug 47%)	no trial arm names this drug
Sensitisation	259	161.6 139.1–187.7ROR 162.2 · calibrated p 3e-9 ✓	105.8 EB05 95.4 · IC025 +6.3 3/3 methods agree	Not in label — unassessed	serious n=259 · ♀ 100% (drug 47%)	no trial arm names this drug
Acquired factor v deficiency	37	157.2 105.8–233.4ROR 157.2 · calibrated p 1e-8 ✓	99.4 EB05 75.3 · IC025 +4.9 3/3 methods agree	Not in label — unassessed	serious n=37 · ♀ 0% (drug 47%) · 100% consumer	no trial arm names this drug
Coagulation factor deficiency	51	145.1 104.0–202.3ROR 145.2 · calibrated p 1e-8 ✓	95.7 EB05 75.6 · IC025 +5.2 3/3 methods agree	Not in label — unassessed	serious n=51 · ♀ 0% (drug 47%)	no trial arm names this drug
Central nervous system lupus	63	129.4 96.4–173.6ROR 129.5 · calibrated p 3e-8 ✓	89.2 EB05 72.2 · IC025 +5.3 3/3 methods agree	Not in label — unassessed	serious n=63 · ♀ 100% (drug 47%)	no trial arm names this drug
Coagulation factor v level abnormal	31	104.5 69.5–157.0ROR 104.5 · calibrated p 2e-7 ✓	74.9 EB05 55.3 · IC025 +4.5 3/3 methods agree	Lab value / disease marker	serious n=31 · ♀ 0% (drug 47%)	no trial arm names this drug
Spirometry abnormal	141	99.6 82.4–120.4ROR 99.8 · calibrated p 1e-7 ✓	74.9 EB05 65.1 · IC025 +5.6 3/3 methods agree	Lab value / disease marker	serious n=141 · ♀ 0% (drug 47%)	no trial arm names this drug
Mite allergy	146	93.5 77.7–112.5ROR 93.7 · calibrated p 2e-7 ✓	71.4 EB05 62.2 · IC025 +5.6 3/3 methods agree	Not in label — unassessed	serious n=146 · ♀ 10% (drug 47%)	no trial arm names this drug
Atrial tachycardia	424	79.3 71.3–88.2ROR 79.8 · calibrated p 6e-7 ✓	63.2 EB05 58.3 · IC025 +5.7 3/3 methods agree	Not in label — unassessed	serious n=424	no trial arm names this drug
Pulmonary vasculitis	90	64.6 51.5–81.1ROR 64.7 · calibrated p 3e-6 ✓	53.1 EB05 44.5 · IC025 +5.0 3/3 methods agree	Not in label — unassessed	serious n=90 · ♀ 0% (drug 47%)	no trial arm names this drug
Human rhinovirus test positive	63	64.0 48.8–84.0ROR 64.1 · calibrated p 4e-6 ✓	52.5 EB05 42.5 · IC025 +4.8 3/3 methods agree	Lab value / disease marker	serious n=63 · ♀ 100% (drug 47%)	no trial arm names this drug
Pruritus genital	388	63.0 56.5–70.2ROR 63.3 · calibrated p 3e-6 ✓	52.4 EB05 48.1 · IC025 +5.5 3/3 methods agree	Not in label — unassessed	serious n=388	no trial arm names this drug
Polycystic ovaries	257	61.6 53.9–70.4ROR 61.8 · calibrated p 4e-6 ✓	51.4 EB05 46.3 · IC025 +5.3 3/3 methods agree	Not in label — unassessed	serious n=257 · ♀ 100% (drug 47%)	no trial arm names this drug
Therapeutic drug monitoring analysis not performed	48	60.5 44.4–82.4ROR 60.5 · calibrated p 6e-6 ✓	49.8 EB05 39.1 · IC025 +4.6 3/3 methods agree	Labeled (related wording) related wording	serious n=48 · 100% clinician	no trial arm names this drug
Mycotic allergy	131	57.9 48.1–69.8ROR 58.1 · calibrated p 6e-6 ✓	48.7 EB05 42.1 · IC025 +5.1 3/3 methods agree	Not in label — unassessed	serious n=131 · ♀ 0% (drug 47%)	no trial arm names this drug
Ivth nerve paralysis	35	57.4 40.0–82.3ROR 57.4 · calibrated p 1e-5 ✓	47.4 EB05 35.7 · IC025 +4.3 3/3 methods agree	Not in label — unassessed	serious n=35 · ♀ 0% (drug 47%) · 100% clinician	no trial arm names this drug
Total lung capacity abnormal	58	56.6 42.8–74.8ROR 56.6 · calibrated p 9e-6 ✓	47.3 EB05 37.9 · IC025 +4.7 3/3 methods agree	Not in label — unassessed	serious n=58 · ♀ 0% (drug 47%)	no trial arm names this drug
Dust allergy	133	50.4 41.9–60.5ROR 50.5 · calibrated p 1e-5 ✓	43.2 EB05 37.4 · IC025 +4.9 3/3 methods agree	Not in label — unassessed	serious n=133 · ♀ 0% (drug 47%)	no trial arm names this drug
Cerebral mass effect	47	47.8 35.1–65.0ROR 47.8 · calibrated p 3e-5 ✓	40.9 EB05 32.0 · IC025 +4.4 3/3 methods agree	Not in label — unassessed	serious n=47 · 100% clinician	no trial arm names this drug
Viral test positive	44	42.9 31.3–58.8ROR 42.9 · calibrated p 5e-5 ✓	37.3 EB05 28.9 · IC025 +4.2 3/3 methods agree	Lab value / disease marker	serious n=44 · ♀ 100% (drug 47%) · 100% clinician	no trial arm names this drug
Carotid artery occlusion	412	39.9 36.0–44.2ROR 40.2 · calibrated p 5e-5 ✓	35.4 EB05 32.6 · IC025 +4.9 3/3 methods agree	Not in label — unassessed	serious n=411	no trial arm names this drug
Adrenal haemorrhage	63	39.5 30.4–51.4ROR 39.6 · calibrated p 7e-5 ✓	34.8 EB05 28.2 · IC025 +4.4 3/3 methods agree	Not in label — unassessed	serious n=62 · 100% clinician	no trial arm names this drug
Anticoagulation drug level increased	36	39.2 27.7–55.4ROR 39.2 · calibrated p 9e-5 ✓	34.3 EB05 25.9 · IC025 +4.0 3/3 methods agree	Lab value / disease marker	100% clinician	no trial arm names this drug
Haemoperitoneum	85	38.2 30.5–47.8ROR 38.2 · calibrated p 8e-5 ✓	33.9 EB05 28.3 · IC025 +4.5 3/3 methods agree	Not in label — unassessed	serious n=85 · 100% clinician	no trial arm names this drug
Pneumonia haemophilus	52	37.6 28.2–50.1ROR 37.6 · calibrated p 1e-4 ✓	33.3 EB05 26.3 · IC025 +4.2 3/3 methods agree	Not in label — unassessed	serious n=52 · ♀ 100% (drug 47%)	no trial arm names this drug
Red blood cell transfusion	42	36.9 26.8–50.8ROR 36.9 · calibrated p 1e-4 ✓	32.6 EB05 25.2 · IC025 +4.1 3/3 methods agree	Labeled (related wording) related wording	serious n=41 · ♀ 0% (drug 47%) · 100% clinician	no trial arm names this drug
Conjunctivitis allergic	152	36.5 30.8–43.1ROR 36.6 · calibrated p 1e-4 ✓	32.6 EB05 28.5 · IC025 +4.6 3/3 methods agree	Not in label — unassessed	serious n=152 · ♀ 0% (drug 47%)	no trial arm names this drug
Bronchial wall thickening	73	35.2 27.6–44.8ROR 35.2 · calibrated p 1e-4 ✓	31.5 EB05 25.9 · IC025 +4.3 3/3 methods agree	Not in label — unassessed	serious n=73 · ♀ 0% (drug 47%)	no trial arm names this drug
Pericardial haemorrhage	220	35.1 30.6–40.4ROR 35.2 · calibrated p 1e-4 ✓	31.6 EB05 28.2 · IC025 +4.7 3/3 methods agree	Labeled (related wording) related wording	serious n=220 · 95% clinician	no trial arm names this drug
Factor v leiden mutation	39	34.2 24.5–47.5ROR 34.2 · calibrated p 2e-4 ✓	30.5 EB05 23.2 · IC025 +4.0 3/3 methods agree	Not in label — unassessed	serious n=39 · ♀ 0% (drug 47%) · 100% consumer	no trial arm names this drug
Sleep terror	395	32.6 29.4–36.2ROR 32.8 · calibrated p 2e-4 ✓	29.6 EB05 27.2 · IC025 +4.7 3/3 methods agree	Not in label — unassessed	serious n=395	no trial arm names this drug
Tension headache	403	32.6 29.4–36.1ROR 32.8 · calibrated p 2e-4 ✓	29.5 EB05 27.2 · IC025 +4.7 3/3 methods agree	Not in label — unassessed	serious n=401	no trial arm names this drug
Right ventricular hypertrophy	84	32.0 25.5–40.0ROR 32.0 · calibrated p 2e-4 ✓	28.9 EB05 24.1 · IC025 +4.3 3/3 methods agree	Not in label — unassessed	serious n=84 · ♀ 0% (drug 47%)	no trial arm names this drug
Systemic infection	150	31.2 26.4–36.9ROR 31.2 · calibrated p 2e-4 ✓	28.3 EB05 24.7 · IC025 +4.4 3/3 methods agree	Not in label — unassessed	serious n=150 · 100% clinician	no trial arm names this drug
Urogenital haemorrhage	33	30.9 21.6–44.2ROR 30.9 · calibrated p 3e-4 ✓	27.8 EB05 20.7 · IC025 +3.7 3/3 methods agree	Not in label — unassessed	serious n=33 · ♀ 0% (drug 47%) · 100% clinician	no trial arm names this drug
Respiratory syncytial virus test positive	63	30.9 23.8–40.0ROR 30.9 · calibrated p 3e-4 ✓	27.9 EB05 22.6 · IC025 +4.1 3/3 methods agree	Lab value / disease marker	serious n=63 · ♀ 100% (drug 47%)	no trial arm names this drug

Trial evidence (ClinicalTrials.gov)

No completed trial with posted adverse-event results was found on ClinicalTrials.gov for Apixaban (searched APIXABAN).

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
Atrial fibrillation	4,089	13.8 13.3–14.2ROR 14.6 · calibrated p 0.008 ✓	13.2 EB05 12.9 · IC025 +3.7 3/3 methods agree	Likely indication confounding term in indications; also in warnings	serious PRR 8.2	no trial arm names this drug
Dyspnoea (shortness of breath)	3,794	2.1 2.1–2.2ROR 2.2 · calibrated p 0.956	2.1 EB05 2.1 · IC025 +1.0 3/3 methods agree	Not in label — unassessed	serious PRR 1.7	no trial arm names this drug
Cerebrovascular accident (stroke)	3,586	6.8 6.6–7.0ROR 7.1 · calibrated p 0.095	6.6 EB05 6.5 · IC025 +2.7 3/3 methods agree	Labeled (related wording) related wording	serious PRR 4.0 · 79% consumer	no trial arm names this drug
Off label use (used outside approved label)	2,919	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 1.1	no trial arm names this drug
Thrombosis	2,862	11.6 11.1–12.0ROR 12.0 · calibrated p 0.017 ✓	11.2 EB05 10.8 · IC025 +3.4 3/3 methods agree	Labeled — boxed warning exact term	serious PRR 7.0 · 84% consumer	no trial arm names this drug
Cardiac disorder	2,516	8.7 8.3–9.0ROR 9.0 · calibrated p 0.047 ✓	8.4 EB05 8.2 · IC025 +3.0 3/3 methods agree	Not in label — unassessed	serious PRR 5.9 · 87% consumer	no trial arm names this drug
Fall	2,438	2.3 2.2–2.4ROR 2.4 · calibrated p 0.870	2.3 EB05 2.2 · IC025 +1.1 3/3 methods agree	Not in label — unassessed	serious PRR 1.6	no trial arm names this drug
Fatigue (tiredness)	2,409	1.0 0.9–1.0ROR 1.0 · calibrated p 0.291	1.0 EB05 0.9 · IC025 -0.1 PRR-only: not supported by EBGM or IC	Not in label — unassessed	serious PRR 1.1	no trial arm names this drug
Death	2,399	0.9 0.8–0.9ROR 0.9 · calibrated p 0.227	0.9 EB05 0.8 · IC025 -0.3 PRR-only: not supported by EBGM or IC	Outcome field, not a reaction boxed warning mentions mortality	serious PRR 0.5	no trial arm names this drug
Dizziness	2,073	1.3 1.3–1.4ROR 1.3 · calibrated p 0.524	1.3 EB05 1.3 · IC025 +0.3	Not in label — unassessed	serious PRR 1.3	no trial arm names this drug
Anaemia (low red blood cells)	2,016	3.4 3.2–3.5ROR 3.4 · calibrated p 0.503	3.3 EB05 3.2 · IC025 +1.7 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 2.1	no trial arm names this drug
Diarrhoea (diarrhea)	1,963	1.0 0.9–1.0ROR 1.0 · calibrated p 0.281	1.0 EB05 0.9 · IC025 -0.1 PRR-only: not supported by EBGM or IC	Not in label — unassessed	serious PRR 1.0	no trial arm names this drug
Nausea	1,841	0.7 0.7–0.8ROR 0.7 · calibrated p 0.144	0.7 EB05 0.7 · IC025 -0.5 PRR-only: not supported by EBGM or IC	Labeled adverse reaction exact term	serious PRR 0.8	no trial arm names this drug
Acute kidney injury (sudden kidney damage)	1,822	3.8 3.6–4.0ROR 3.9 · calibrated p 0.400	3.8 EB05 3.6 · IC025 +1.8 3/3 methods agree	Not in label — unassessed	serious PRR 2.3 · 94% clinician	no trial arm names this drug
Drug ineffective (drug did not work)	1,804	0.4 0.4–0.5ROR 0.4 · calibrated p 0.026 ✓	0.4 EB05 0.4 · IC025 -1.3 PRR-only: not supported by EBGM or IC	Reporting / coding artifact	serious PRR 0.7	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.

Cardiospasm — n=397, PRR 799.3
Right atrial hypertrophy — n=75, PRR 664.4
Immunisation — n=262, PRR 489.4
Palmoplantar keratoderma — n=389, PRR 374.6
Ejection fraction — n=216, PRR 185.5
Sensitisation — n=259, PRR 161.6
Acquired factor v deficiency — n=37, PRR 157.2
Coagulation factor deficiency — n=51, PRR 145.1
Central nervous system lupus — n=63, PRR 129.4
Mite allergy — n=146, PRR 93.5

✓ A hand-written Bradford Hill causality assessment exists for this drug: Apixaban ↔ Gastrointestinal bleeding.

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 Apixaban?

In FDA FAERS, the most frequently co-reported reaction terms for Apixaban are atrial fibrillation, dyspnoea, cerebrovascular accident, thrombosis, cardiac disorder, 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 Apixaban have an FDA boxed warning?

Yes. The current FDA label carries a boxed warning: WARNING: (A) PREMATURE DISCONTINUATION OF APIXABAN INCREASES THE RISK OF THROMBOTIC EVENTS (B) SPINAL/EPIDURAL HEMATOMA (A) PREMATURE DISCONTINUATION OF APIXABAN INCREASES THE RISK OF THROMBOTIC EVENTS Premature discontinuation of any oral anticoagulant, including apixaban, increases the risk of thrombotic events.

Do FAERS signals prove that Apixaban 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 095a08ac-cf0e-497e-a682-ddef38d6b29c, effective 20210615; matched on openfda.generic_name.exact:"APIXABAN")
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, 1,254 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 APIXABAN, 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.