Drug · FAERS side-effect profile with label screen

Famotidine, Carbonate and Hydroxide Chewable side effects: what 2,062 FDA adverse event reports show

Famotidine, Calcium Carbonate, Magnesium Hydroxide Chewable Tablet · 39 reaction terms · 2,092 drug–reaction co-reports · data 2026-09-14

Drug class

Histamine-2 Receptor Antagonist

FDA label (Established Pharmacologic Class) · compare the class

Who reports

2,062 reports · 37% serious · 64 with death outcome · 66% female

openFDA FAERS counts, all years, deduplication not applied

Used for

Famotidine for oral suspension is indicated in adults for the treatment of: active duodenal ulcer (DU). active gastric ulcer (GU). symptomatic nonerosive gastroesophageal reflux disease (GERD). erosive esophagitis due to GERD, diagnosed by biopsy. treatment of pathological hypersecretory conditions (e.g., Zollinger-Ellison syndrome, multiple endocrine neoplasias). reduction of the risk of duodenal ulcer recurrence.

FDA label, Indications and Usage

What it is

The active ingredient in famotidine for oral suspension USP is a histamine-2 (H2) receptor antagonist. Famotidine is N' -(aminosulfonyl)-3-[[[2-[(diaminomethylene)amino]-4- thiazolyl]methyl]thio] propanimidamide.

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 27 strongest signals

Labeled (related wording) 2Reporting / coding artifact 15Not in label — unassessed 10

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.
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. 12 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
End stage renal disease	121	67.0 56.4–79.7ROR 71.1 · χ² 7,761 / p <1e-300	65.9 EB05 56.7 · IC025 +5.4 3/3 methods agree	Not in label — unassessed	serious PRR 104.4	no trial data cached
Chronic kidney disease	443	58.9 54.3–64.0ROR 74.7 · χ² 25,118 / p <1e-300	58.5 EB05 54.0 · IC025 +5.6 3/3 methods agree	Not in label — unassessed	serious PRR 93.3	no trial data cached
Product physical issue	78	39.8 32.0–49.5ROR 41.4 · χ² 2,905 / p <1e-300	39.3 EB05 32.5 · IC025 +4.6 3/3 methods agree	Reporting / coding artifact	97% consumer	no trial data cached
Product packaging issue	21	23.0 15.0–35.2ROR 23.2 · χ² 419 / p 2e-93	22.5 EB05 15.5 · IC025 +3.2 3/3 methods agree	Reporting / coding artifact	serious n=1 · 100% consumer	no trial data cached
Renal injury	67	22.7 17.9–28.7ROR 23.4 · χ² 1,366 / p 3e-299	22.5 EB05 18.3 · IC025 +3.9 3/3 methods agree	Not in label — unassessed	serious PRR 35.6	no trial data cached
Tubulointerstitial nephritis	37	20.1 14.6–27.6ROR 20.4 · χ² 651 / p 8e-144	19.8 EB05 15.0 · IC025 +3.5 3/3 methods agree	Not in label — unassessed	serious PRR 31.5	no trial data cached
Poor quality product administered	20	19.9 12.8–30.8ROR 20.1 · χ² 339 / p 4e-76	19.4 EB05 13.1 · IC025 +3.0 3/3 methods agree	Not in label — unassessed	95% consumer	no trial data cached
Therapeutic response unexpected	88	19.9 16.2–24.4ROR 20.7 · χ² 1,557 / p <1e-300	19.7 EB05 16.5 · IC025 +3.8 3/3 methods agree	Reporting / coding artifact	serious PRR 1.4 · 97% consumer	no trial data cached
Product taste abnormal	24	18.1 12.2–27.0ROR 18.3 · χ² 371 / p 6e-83	17.8 EB05 12.4 · IC025 +3.1 3/3 methods agree	Reporting / coding artifact	serious n=2 · 87% consumer	no trial data cached
Nephropathy	16	17.3 10.6–28.2ROR 17.4 · χ² 230 / p 4e-52	16.7 EB05 10.4 · IC025 +2.7 3/3 methods agree	Not in label — unassessed	serious PRR 28.9	no trial data cached
Acute kidney injury (sudden kidney damage)	238	15.9 14.1–17.9ROR 17.8 · χ² 3,320 / p <1e-300	15.8 EB05 14.2 · IC025 +3.7 3/3 methods agree	Labeled (related wording) related wording	serious PRR 24.9	no trial data cached
Gastrooesophageal reflux disease (acid reflux)	121	15.3 12.9–18.2ROR 16.2 · χ² 1,609 / p <1e-300	15.2 EB05 13.1 · IC025 +3.6 3/3 methods agree	Not in label — unassessed	serious PRR 31.3 · 76% consumer	no trial data cached
Accidental overdose	48	13.3 10.1–17.6ROR 13.6 · χ² 535 / p 9e-119	13.1 EB05 10.1 · IC025 +3.1 3/3 methods agree	Reporting / coding artifact	serious PRR 25.1 · 100% consumer	no trial data cached
Renal failure (kidney failure)	151	11.5 9.8–13.4ROR 12.3 · χ² 1,438 / p <1e-300	11.4 EB05 9.9 · IC025 +3.2 3/3 methods agree	Labeled (related wording) related wording	serious PRR 18.1	no trial data cached
Dysgeusia (altered taste)	67	9.1 7.2–11.5ROR 9.4 · χ² 476 / p 6e-106	8.8 EB05 7.1 · IC025 +2.7 3/3 methods agree	Not in label — unassessed	serious PRR 1.2 · 94% consumer	no trial data cached
Exposure during pregnancy	53	8.6 6.6–11.3ROR 8.8 · χ² 352 / p 9e-79	8.2 EB05 6.5 · IC025 +2.6 3/3 methods agree	Reporting / coding artifact	♀ 100% (drug 66%) · 100% consumer	no trial data cached
Incorrect drug administration duration	21	7.5 4.9–11.4ROR 7.5 · χ² 111 / p 2e-26	6.6 EB05 4.5 · IC025 +2.0 3/3 methods agree	Reporting / coding artifact	serious PRR 3.1 · 95% consumer	no trial data cached
Drug effect incomplete	26	7.2 4.9–10.5ROR 7.2 · χ² 132 / p 8e-31	6.5 EB05 4.6 · IC025 +2.0 3/3 methods agree	Reporting / coding artifact	100% consumer	no trial data cached
Incorrect product administration duration	13	6.5 3.8–11.2ROR 6.5 · χ² 55 / p 6e-14	5.4 EB05 3.3 · IC025 +1.5 3/3 methods agree	Reporting / coding artifact	–	no trial data cached
Dyspepsia (indigestion)	60	6.2 4.8–8.0ROR 6.4 · χ² 258 / p 3e-58	5.9 EB05 4.8 · IC025 +2.1 3/3 methods agree	Not in label — unassessed	serious PRR 5.2 · 84% consumer	no trial data cached
Expired product administered	20	6.1 4.0–9.5ROR 6.2 · χ² 81 / p 1e-19	5.4 EB05 3.7 · IC025 +1.7 3/3 methods agree	Reporting / coding artifact	100% consumer	no trial data cached
Contraindicated product administered	17	5.7 3.6–9.2ROR 5.8 · χ² 62 / p 2e-15	5.0 EB05 3.3 · IC025 +1.5 3/3 methods agree	Reporting / coding artifact	serious PRR 1.3	no trial data cached
Retching	11	5.2 2.9–9.5ROR 5.3 · χ² 34 / p 3e-9	4.4 EB05 2.6 · IC025 +1.1 3/3 methods agree	Not in label — unassessed	serious PRR 1.5	no trial data cached
Wrong technique in product usage process	81	4.1 3.3–5.0ROR 4.2 · χ² 186 / p 1e-42	4.0 EB05 3.3 · IC025 +1.6 3/3 methods agree	Reporting / coding artifact	99% consumer	no trial data cached
Incorrect dose administered	85	3.8 3.1–4.7ROR 4.0 · χ² 177 / p 1e-40	3.8 EB05 3.1 · IC025 +1.6 3/3 methods agree	Reporting / coding artifact	serious PRR 0.3 · 98% consumer	no trial data cached
Accidental exposure to product	37	3.8 2.7–5.2ROR 3.8 · χ² 72 / p 9e-18	3.6 EB05 2.7 · IC025 +1.3 3/3 methods agree	Reporting / coding artifact	100% consumer	no trial data cached
Overdose	56	2.6 2.0–3.4ROR 2.7 · χ² 55 / p 6e-14	2.6 EB05 2.1 · IC025 +0.9 3/3 methods agree	Reporting / coding artifact	serious PRR 0.4 · 95% consumer	no trial data cached

Trial evidence (ClinicalTrials.gov)

Trial cross-check not yet run for this drug (ClinicalTrials.gov pull covers the 800 most-reported drugs first).

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
Chronic kidney disease	443	58.9 54.3–64.0ROR 74.7 · χ² 25,118 / p <1e-300	58.5 EB05 54.0 · IC025 +5.6 3/3 methods agree	Not in label — unassessed	serious PRR 93.3	no trial data cached
Acute kidney injury (sudden kidney damage)	238	15.9 14.1–17.9ROR 17.8 · χ² 3,320 / p <1e-300	15.8 EB05 14.2 · IC025 +3.7 3/3 methods agree	Labeled (related wording) related wording	serious PRR 24.9	no trial data cached
Renal failure (kidney failure)	151	11.5 9.8–13.4ROR 12.3 · χ² 1,438 / p <1e-300	11.4 EB05 9.9 · IC025 +3.2 3/3 methods agree	Labeled (related wording) related wording	serious PRR 18.1	no trial data cached
Gastrooesophageal reflux disease (acid reflux)	121	15.3 12.9–18.2ROR 16.2 · χ² 1,609 / p <1e-300	15.2 EB05 13.1 · IC025 +3.6 3/3 methods agree	Not in label — unassessed	serious PRR 31.3 · 76% consumer	no trial data cached
End stage renal disease	121	67.0 56.4–79.7ROR 71.1 · χ² 7,761 / p <1e-300	65.9 EB05 56.7 · IC025 +5.4 3/3 methods agree	Not in label — unassessed	serious PRR 104.4	no trial data cached
Therapeutic response unexpected	88	19.9 16.2–24.4ROR 20.7 · χ² 1,557 / p <1e-300	19.7 EB05 16.5 · IC025 +3.8 3/3 methods agree	Reporting / coding artifact	serious PRR 1.4 · 97% consumer	no trial data cached
Incorrect dose administered	85	3.8 3.1–4.7ROR 4.0 · χ² 177 / p 1e-40	3.8 EB05 3.1 · IC025 +1.6 3/3 methods agree	Reporting / coding artifact	serious PRR 0.3 · 98% consumer	no trial data cached
Wrong technique in product usage process	81	4.1 3.3–5.0ROR 4.2 · χ² 186 / p 1e-42	4.0 EB05 3.3 · IC025 +1.6 3/3 methods agree	Reporting / coding artifact	99% consumer	no trial data cached
Product physical issue	78	39.8 32.0–49.5ROR 41.4 · χ² 2,905 / p <1e-300	39.3 EB05 32.5 · IC025 +4.6 3/3 methods agree	Reporting / coding artifact	97% consumer	no trial data cached
Dysgeusia (altered taste)	67	9.1 7.2–11.5ROR 9.4 · χ² 476 / p 6e-106	8.8 EB05 7.1 · IC025 +2.7 3/3 methods agree	Not in label — unassessed	serious PRR 1.2 · 94% consumer	no trial data cached
Renal injury	67	22.7 17.9–28.7ROR 23.4 · χ² 1,366 / p 3e-299	22.5 EB05 18.3 · IC025 +3.9 3/3 methods agree	Not in label — unassessed	serious PRR 35.6	no trial data cached
Dyspepsia (indigestion)	60	6.2 4.8–8.0ROR 6.4 · χ² 258 / p 3e-58	5.9 EB05 4.8 · IC025 +2.1 3/3 methods agree	Not in label — unassessed	serious PRR 5.2 · 84% consumer	no trial data cached
Overdose	56	2.6 2.0–3.4ROR 2.7 · χ² 55 / p 6e-14	2.6 EB05 2.1 · IC025 +0.9 3/3 methods agree	Reporting / coding artifact	serious PRR 0.4 · 95% consumer	no trial data cached
Exposure during pregnancy	53	8.6 6.6–11.3ROR 8.8 · χ² 352 / p 9e-79	8.2 EB05 6.5 · IC025 +2.6 3/3 methods agree	Reporting / coding artifact	♀ 100% (drug 66%) · 100% consumer	no trial data cached
Accidental overdose	48	13.3 10.1–17.6ROR 13.6 · χ² 535 / p 9e-119	13.1 EB05 10.1 · IC025 +3.1 3/3 methods agree	Reporting / coding artifact	serious PRR 25.1 · 100% consumer	no trial data cached

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.

End stage renal disease — n=121, PRR 67.0
Chronic kidney disease — n=443, PRR 58.9
Renal injury — n=67, PRR 22.7
Tubulointerstitial nephritis — n=37, PRR 20.1
Poor quality product administered — n=20, PRR 19.9
Gastrooesophageal reflux disease — n=121, PRR 15.3
Dysgeusia — n=67, PRR 9.1
Dyspepsia — n=60, PRR 6.2

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 Famotidine?

In FDA FAERS, the most frequently co-reported reaction terms for Famotidine are chronic kidney disease, acute kidney injury, renal failure, gastrooesophageal reflux disease, end stage renal disease, dysgeusia. 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 Famotidine have an FDA boxed warning?

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

Do FAERS signals prove that Famotidine 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 04aaf296-f136-29d7-e063-6294a90affe1, effective 20230907; matched on openfda.generic_name.exact:"FAMOTIDINE")
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, 39 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

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.