Drug · FAERS side-effect profile with label screen
Famotidine side effects: what 116,682 FDA adverse event reports show
Drug class
Histamine-2 Receptor Antagonist
FDA label (Established Pharmacologic Class) · compare the class
Who reports
116,682 reports · 64% serious · 10,682 with death outcome · 62% 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 40 strongest signals
Labeled (related wording) 4Likely indication confounding 3Reporting / coding artifact 2Lab value / disease marker 1Not 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.
- 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). 1,119 further terms are in the interactive explorer. Reaction links open the term's cross-drug page.
Show:
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Chronic kidney disease-mineral and bone disorder | 241 | 51.7 44.8–59.7ROR 51.8 · calibrated p 1e-5 ✓ | 40.1 EB05 36.0 · IC025 +5.0 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 81.0 (58.4–112.4) | Not in label — unassessed | serious n=241 | not reported in cached trials |
| Nephrogenic anaemia | 880 | 41.5 38.6–44.7ROR 41.8 · calibrated p 4e-5 ✓ | 33.8 EB05 31.9 · IC025 +4.9 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 97.8 (81.3–117.8) | Not in label — unassessed | serious n=881 · 100% clinician | not reported in cached trials |
| Rebound acid hypersecretion | 552 | 39.3 35.8–43.1ROR 39.5 · calibrated p 6e-5 ✓ | 32.3 EB05 30.1 · IC025 +4.8 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 73.5 (59.8–90.5) | Likely indication confounding shares a disease stem with the indications wording | serious n=550 | not reported in cached trials |
| Hyperparathyroidism secondary | 440 | 37.6 34.0–41.7ROR 37.8 · calibrated p 8e-5 ✓ | 31.2 EB05 28.8 · IC025 +4.8 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 94.1 (72.7–121.9) | Not in label — unassessed | serious n=439 | not reported in cached trials |
| Mast cell activation syndrome | 189 | 29.8 25.5–34.7ROR 29.8 · calibrated p 3e-4 ✓ | 25.6 EB05 22.6 · IC025 +4.3 3/3 methods agree vs other Histamine-2 Receptor Antagonists: only this drug | Not in label — unassessed | serious n=179 · ♀ 100% (drug 62%) | not reported in cached trials |
| End stage renal disease | 2,009 | 21.9 20.9–22.9ROR 22.3 · calibrated p 0.001 ✓ | 19.6 EB05 18.9 · IC025 +4.2 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 51.2 (46.6–56.2) | Not in label — unassessed | serious PRR 17.6 | not reported in cached trials |
| Chronic kidney disease | 6,660 | 17.0 16.6–17.4ROR 18.0 · calibrated p 0.003 ✓ | 15.6 EB05 15.3 · IC025 +3.9 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 45.1 (43.1–47.3) | Not in label — unassessed | age-adj. PRR 15.1 · serious PRR 14.3 | not reported in cached trials |
| Infusion site discharge | 130 | 14.7 12.3–17.6ROR 14.7 · calibrated p 0.008 ✓ | 13.6 EB05 11.7 · IC025 +3.4 3/3 methods agree vs other Histamine-2 Receptor Antagonists: only this drug | Not in label — unassessed | serious n=82 · ♀ 100% (drug 62%) · 100% consumer | not reported in cached trials |
| Accidental drug intake by child | 96 | 11.8 9.6–14.4ROR 11.8 · calibrated p 0.019 ✓ | 10.9 EB05 9.1 · IC025 +3.1 3/3 methods agree vs other Histamine-2 Receptor Antagonists: only this drug | Not in label — unassessed | ♀ 0% (drug 62%) · 100% consumer | not reported in cached trials |
| Aplastic anaemia | 306 | 11.1 9.9–12.4ROR 11.1 · calibrated p 0.023 ✓ | 10.4 EB05 9.5 · IC025 +3.2 3/3 methods agree vs other Histamine-2 Receptor Antagonists: only this drug | Not in label — unassessed | serious n=306 · 100% clinician | not reported in cached trials |
| Calcium deficiency | 74 | 10.8 8.5–13.6ROR 10.8 · calibrated p 0.027 ✓ | 9.9 EB05 8.1 · IC025 +2.9 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 29.9 (20.0–44.6) | Not in label — unassessed | serious n=67 · ♀ 100% (drug 62%) | not reported in cached trials |
| Renal injury | 1,498 | 9.4 8.9–9.9ROR 9.5 · calibrated p 0.039 ✓ | 8.9 EB05 8.6 · IC025 +3.1 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 49.2 (44.2–54.7) | Not in label — unassessed | serious PRR 8.1 | not reported in cached trials |
| Infusion site haemorrhage | 151 | 8.7 7.4–10.3ROR 8.7 · calibrated p 0.052 | 8.2 EB05 7.2 · IC025 +2.8 3/3 methods agree vs other Histamine-2 Receptor Antagonists: only this drug | Not in label — unassessed | serious n=79 · 100% consumer | not reported in cached trials |
| Infusion site swelling | 262 | 7.9 7.0–9.0ROR 8.0 · calibrated p 0.069 | 7.6 EB05 6.8 · IC025 +2.7 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 217.6 (133.3–355.4) | Not in label — unassessed | serious n=125 · 76% consumer | not reported in cached trials |
| Infusion site pruritus | 129 | 7.7 6.5–9.2ROR 7.7 · calibrated p 0.076 | 7.3 EB05 6.3 · IC025 +2.6 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 165.6 (89.5–306.4) | Labeled (related wording) related wording | serious n=83 · ♀ 100% (drug 62%) · 100% consumer | NCT01499368: 1/165 (0.6%) on Famotidine |
| Tubulointerstitial nephritis | 747 | 7.4 6.9–8.0ROR 7.5 · calibrated p 0.082 | 7.1 EB05 6.7 · IC025 +2.7 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 55.2 (47.1–64.7) | Not in label — unassessed | age-adj. PRR 4.4 · serious PRR 6.5 | not reported in cached trials |
| Infusion site bruising | 84 | 7.3 5.9–9.1ROR 7.3 · calibrated p 0.089 | 6.9 EB05 5.7 · IC025 +2.4 3/3 methods agree vs other Histamine-2 Receptor Antagonists: only this drug | Not in label — unassessed | serious n=60 · ♀ 100% (drug 62%) · 100% consumer | not reported in cached trials |
| Device infusion issue | 90 | 6.8 5.5–8.4ROR 6.8 · calibrated p 0.110 | 6.4 EB05 5.4 · IC025 +2.3 3/3 methods agree vs other Histamine-2 Receptor Antagonists: only this drug | Reporting / coding artifact | ♀ 100% (drug 62%) · 100% consumer | not reported in cached trials |
| Infusion site pain | 466 | 6.8 6.2–7.4ROR 6.8 · calibrated p 0.108 | 6.5 EB05 6.0 · IC025 +2.6 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 193.5 (136.7–274.1) | Labeled (related wording) related wording | age-adj. PRR 5.6 · serious n=227 · 79% consumer | NCT01499368: 1/167 (0.6%) on Famotidine (serious AE) |
| Gastrointestinal hypomotility | 80 | 6.6 5.3–8.3ROR 6.6 · calibrated p 0.118 | 6.2 EB05 5.2 · IC025 +2.3 3/3 methods agree vs other Histamine-2 Receptor Antagonists: only this drug | Not in label — unassessed | serious n=79 · ♀ 100% (drug 62%) | not reported in cached trials |
| Infusion site erythema | 296 | 6.6 5.9–7.4ROR 6.6 · calibrated p 0.116 | 6.4 EB05 5.8 · IC025 +2.5 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 418.0 (222.6–784.8) | Not in label — unassessed | serious n=152 · 78% consumer | not reported in cached trials |
| Essential hypertension | 89 | 6.4 5.1–7.9ROR 6.4 · calibrated p 0.133 | 6.0 EB05 5.0 · IC025 +2.2 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 104.7 (57.3–191.3) | Not in label — unassessed | serious n=83 · ♀ 0% (drug 62%) · 100% clinician | NCT01499368: 1/162 (0.6%) on Famotidine |
| Impaired gastric emptying | 413 | 6.0 5.4–6.6ROR 6.0 · calibrated p 0.151 | 5.8 EB05 5.3 · IC025 +2.4 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 448.6 (258.3–779.0) | Likely indication confounding shares a disease stem with the indications wording | serious PRR 5.8 · 75% consumer | not reported in cached trials |
| Infusion site infection | 73 | 5.9 4.7–7.5ROR 5.9 · calibrated p 0.159 | 5.6 EB05 4.6 · IC025 +2.1 3/3 methods agree vs other Histamine-2 Receptor Antagonists: only this drug | Not in label — unassessed | 100% consumer | NCT01499368: 2/162 (1.2%) on Famotidine |
| Gastrooesophageal reflux disease (acid reflux) | 2,528 | 5.8 5.6–6.0ROR 5.9 · calibrated p 0.155 | 5.7 EB05 5.5 · IC025 +2.4 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 64.7 (59.0–70.8) | Not in label — unassessed | age-adj. PRR 5.1 · serious PRR 6.1 | NCT01499368: 1/162 (0.6%) on Famotidine |
| Rhinovirus infection | 119 | 5.8 4.8–6.9ROR 5.8 · calibrated p 0.169 | 5.5 EB05 4.7 · IC025 +2.2 3/3 methods agree vs other Histamine-2 Receptor Antagonists: only this drug | Not in label — unassessed | serious n=116 | not reported in cached trials |
| Acute kidney injury (sudden kidney damage) | 4,727 | 5.7 5.6–5.9ROR 5.9 · calibrated p 0.155 | 5.6 EB05 5.4 · IC025 +2.4 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 59.8 (56.1–63.8) | Labeled (related wording) related wording | age-adj. PRR 3.2 · serious PRR 5.0 | not reported in cached trials |
| Renal failure (kidney failure) | 4,119 | 5.7 5.5–5.8ROR 5.8 · calibrated p 0.160 | 5.5 EB05 5.4 · IC025 +2.4 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 59.1 (55.2–63.3) | Labeled (related wording) related wording | age-adj. PRR 3.7 · serious PRR 5.0 | not reported in cached trials |
| Nephropathy | 280 | 5.5 4.9–6.2ROR 5.5 · calibrated p 0.188 | 5.3 EB05 4.8 · IC025 +2.2 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 62.8 (47.8–82.5) | Not in label — unassessed | serious PRR 5.1 | not reported in cached trials |
| Hypervolaemia | 143 | 5.5 4.6–6.5ROR 5.5 · calibrated p 0.191 | 5.3 EB05 4.6 · IC025 +2.1 3/3 methods agree vs other Histamine-2 Receptor Antagonists: only this drug | Not in label — unassessed | serious n=138 | not reported in cached trials |
| Peptic ulcer | 97 | 5.4 4.4–6.6ROR 5.4 · calibrated p 0.202 | 5.1 EB05 4.3 · IC025 +2.0 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 54.8 (35.3–85.0) | Likely indication confounding term in indications | serious n=93 · ♀ 100% (drug 62%) | not reported in cached trials |
| Seasonal allergy | 399 | 5.2 4.7–5.7ROR 5.2 · calibrated p 0.214 | 5.0 EB05 4.6 · IC025 +2.2 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 281.7 (179.8–441.3) | Not in label — unassessed | serious n=233 · 74% consumer | not reported in cached trials |
| Atelectasis | 267 | 5.1 4.5–5.7ROR 5.1 · calibrated p 0.229 | 4.9 EB05 4.4 · IC025 +2.1 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 114.2 (79.6–164.0) | Not in label — unassessed | age-adj. PRR 4.6 · serious PRR 4.5 | not reported in cached trials |
| Infusion site reaction | 80 | 5.1 4.0–6.3ROR 5.1 · calibrated p 0.234 | 4.8 EB05 4.0 · IC025 +1.9 3/3 methods agree vs other Histamine-2 Receptor Antagonists: only this drug | Not in label — unassessed | 100% consumer | not reported in cached trials |
| Product administration interrupted | 207 | 5.0 4.3–5.7ROR 5.0 · calibrated p 0.241 | 4.8 EB05 4.3 · IC025 +2.0 3/3 methods agree vs other Histamine-2 Receptor Antagonists: only this drug | Reporting / coding artifact | serious n=170 | not reported in cached trials |
| Monocyte count increased | 96 | 4.8 4.0–5.9ROR 4.8 · calibrated p 0.257 | 4.6 EB05 3.9 · IC025 +1.9 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 96.8 (55.3–169.6) | Lab value / disease marker | serious n=88 · 100% clinician | not reported in cached trials |
| Vitamin d deficiency | 253 | 4.8 4.2–5.4ROR 4.8 · calibrated p 0.263 | 4.6 EB05 4.2 · IC025 +2.0 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 52.5 (40.2–68.6) | Not in label — unassessed | serious PRR 4.6 | not reported in cached trials |
| Cholecystitis chronic | 176 | 4.8 4.1–5.5ROR 4.8 · calibrated p 0.265 | 4.6 EB05 4.1 · IC025 +2.0 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 130.8 (81.5–209.9) | Not in label — unassessed | serious PRR 4.2 · ♀ 100% (drug 62%) | not reported in cached trials |
| Renal tubular necrosis | 255 | 4.8 4.2–5.4ROR 4.8 · calibrated p 0.264 | 4.6 EB05 4.2 · IC025 +2.0 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 55.4 (42.2–72.7) | Not in label — unassessed | age-adj. PRR 3.0 · serious PRR 4.2 · 100% clinician | not reported in cached trials |
| Metabolic encephalopathy | 77 | 4.7 3.8–5.9ROR 4.7 · calibrated p 0.275 | 4.5 EB05 3.7 · IC025 +1.8 3/3 methods agree vs other Histamine-2 Receptor Antagonists: only this drug | Not in label — unassessed | serious n=76 · ♀ 0% (drug 62%) · 100% clinician | not reported in cached trials |
Clinical concept groups
MedDRA splits one clinical problem across several terms (e.g. "neutropenia", "neutrophil count decreased", "agranulocytosis"), which dilutes term-level signals. These rows count reports with any term in a concept group (an exact union, not a sum), compared with all other drugs. Groups are hand-built and listed in the methods.
| Concept | Reports | PRR 95% CI | Reading |
|---|---|---|---|
| Kidney injury | 9,086 | 3.63.6–3.7 | signal |
| Anaphylaxis / angioedema | 1,638 | 2.42.3–2.5 | signal |
| Anaemia | 3,679 | 2.22.1–2.3 | signal |
| Hyponatraemia | 983 | 2.22.1–2.3 | signal |
| Thrombocytopenia | 2,686 | 2.22.1–2.3 | signal |
| Interstitial lung disease | 1,098 | 2.11.9–2.2 | raised |
| Neutropenia / agranulocytosis | 2,817 | 2.12.0–2.1 | raised |
| Serious infection | 8,346 | 2.01.9–2.0 | raised |
| Arrhythmia / qt | 1,897 | 1.81.7–1.8 | raised |
| Gi bleeding | 1,721 | 1.71.6–1.8 | raised |
| Depression | 2,507 | 1.61.5–1.7 | raised |
| Venous thromboembolism | 1,873 | 1.61.5–1.6 | raised |
| Heart failure | 1,541 | 1.61.5–1.6 | raised |
| Fall / fracture | 3,248 | 1.51.5–1.6 | raised |
| Pancreatitis | 676 | 1.51.4–1.6 | raised |
| Rhabdomyolysis / myopathy | 679 | 1.51.4–1.6 | raised |
Trial evidence (ClinicalTrials.gov)
✓ Trial adverse-event data found on ClinicalTrials.gov
Largest completed trials with posted results that list Famotidine 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 (5 of 40 signal terms matched).
- NCT01499368 — A Multi-center, Randomized, Double-blind Phase III Clinical Trial to Assess and Compare to the Efficacy and Sa (N=495, PHASE3; 72 AE terms posted; arms: Lafutidine; Famotidine; Omeprazole)
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 |
|---|---|---|---|---|---|---|
| Nausea | 7,797 | 1.8 1.7–1.8ROR 1.8 · calibrated p 0.852 | 1.8 EB05 1.7 · IC025 +0.8 vs other Histamine-2 Receptor Antagonists: PRR 155.3 (143.9–167.5) | Labeled adverse reaction exact term | age-adj. PRR 1.8 · serious PRR 2.0 | NCT01499368: 1/162 (0.6%) on Famotidine |
| Fatigue (tiredness) | 7,353 | 1.7 1.7–1.7ROR 1.8 · calibrated p 0.802 | 1.7 EB05 1.7 · IC025 +0.7 vs other Histamine-2 Receptor Antagonists: PRR 164.5 (151.9–178.3) | Labeled adverse reaction exact term | age-adj. PRR 1.6 · serious PRR 1.7 | NCT01499368: 1/162 (0.6%) on Famotidine |
| Diarrhoea (diarrhea) | 7,011 | 2.0 1.9–2.0ROR 2.0 · calibrated p 0.960 | 2.0 EB05 1.9 · IC025 +0.9 vs other Histamine-2 Receptor Antagonists: PRR 211.5 (192.8–232.1) | Labeled adverse reaction exact term | age-adj. PRR 1.8 · serious PRR 1.9 | NCT01499368: 2/167 (1.2%) on Famotidine |
| Chronic kidney disease | 6,660 | 17.0 16.6–17.4ROR 18.0 · calibrated p 0.003 ✓ | 15.6 EB05 15.3 · IC025 +3.9 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 45.1 (43.1–47.3) | Not in label — unassessed | age-adj. PRR 15.1 · serious PRR 14.3 | not reported in cached trials |
| Drug ineffective (drug did not work) | 6,551 | 0.9 0.9–0.9ROR 0.9 · calibrated p 0.235 | 0.9 EB05 0.9 · IC025 -0.2 PRR-only: not supported by EBGM or IC vs other Histamine-2 Receptor Antagonists: PRR 176.5 (161.7–192.8) | Reporting / coding artifact | age-adj. PRR 0.9 · serious PRR 0.8 | not reported in cached trials |
| Off label use (used outside approved label) | 5,672 | 1.2 1.1–1.2ROR 1.2 · calibrated p 0.429 | 1.2 EB05 1.1 · IC025 +0.2 vs other Histamine-2 Receptor Antagonists: PRR 206.4 (186.4–228.6) | Reporting / coding artifact | age-adj. PRR 1.1 · serious PRR 1.1 | not reported in cached trials |
| Dyspnoea (shortness of breath) | 5,610 | 1.8 1.7–1.8ROR 1.8 · calibrated p 0.847 | 1.8 EB05 1.7 · IC025 +0.8 vs other Histamine-2 Receptor Antagonists: PRR 152.9 (139.9–167.2) | Not in label — unassessed | age-adj. PRR 1.7 · serious PRR 1.7 | not reported in cached trials |
| Headache | 5,357 | 1.5 1.5–1.6ROR 1.6 · calibrated p 0.685 | 1.5 EB05 1.5 · IC025 +0.6 vs other Histamine-2 Receptor Antagonists: PRR 193.5 (174.7–214.2) | Labeled adverse reaction exact term | age-adj. PRR 1.5 · serious PRR 1.6 | NCT01499368: 3/162 (1.9%) on Famotidine |
| Pain | 4,875 | 1.4 1.4–1.5ROR 1.4 · calibrated p 0.605 | 1.4 EB05 1.4 · IC025 +0.5 vs other Histamine-2 Receptor Antagonists: PRR 151.0 (137.3–166.0) | Labeled adverse reaction exact term | age-adj. PRR 1.6 · serious PRR 1.5 | NCT01499368: 1/167 (0.6%) on Famotidine (serious AE) |
| Vomiting | 4,751 | 1.8 1.8–1.9ROR 1.9 · calibrated p 0.867 | 1.8 EB05 1.8 · IC025 +0.8 vs other Histamine-2 Receptor Antagonists: PRR 132.3 (120.9–144.9) | Labeled adverse reaction exact term | age-adj. PRR 1.8 · serious PRR 1.8 | NCT01499368: 1/162 (0.6%) on Famotidine |
| Acute kidney injury (sudden kidney damage) | 4,727 | 5.7 5.6–5.9ROR 5.9 · calibrated p 0.155 | 5.6 EB05 5.4 · IC025 +2.4 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 59.8 (56.1–63.8) | Labeled (related wording) related wording | age-adj. PRR 3.2 · serious PRR 5.0 | not reported in cached trials |
| Dizziness | 4,526 | 1.6 1.6–1.7ROR 1.7 · calibrated p 0.747 | 1.6 EB05 1.6 · IC025 +0.7 vs other Histamine-2 Receptor Antagonists: PRR 159.8 (144.4–176.8) | Labeled adverse reaction exact term | age-adj. PRR 1.5 · serious PRR 1.6 | NCT01499368: 1/162 (0.6%) on Famotidine |
| Renal failure (kidney failure) | 4,119 | 5.7 5.5–5.8ROR 5.8 · calibrated p 0.160 | 5.5 EB05 5.4 · IC025 +2.4 3/3 methods agree vs other Histamine-2 Receptor Antagonists: PRR 59.1 (55.2–63.3) | Labeled (related wording) related wording | age-adj. PRR 3.7 · serious PRR 5.0 | not reported in cached trials |
| Death | 3,897 | 0.8 0.8–0.8ROR 0.8 · calibrated p 0.187 | 0.8 EB05 0.8 · IC025 -0.4 PRR-only: not supported by EBGM or IC vs other Histamine-2 Receptor Antagonists: PRR 133.2 (120.5–147.3) | Outcome field, not a reaction | age-adj. PRR 0.9 · serious PRR 0.7 | not reported in cached trials |
| Pneumonia (lung infection) | 3,684 | 2.1 2.0–2.1ROR 2.1 · calibrated p 0.994 | 2.0 EB05 2.0 · IC025 +1.0 vs other Histamine-2 Receptor Antagonists: PRR 172.2 (153.3–193.6) | Labeled adverse reaction exact term | age-adj. PRR 1.9 · serious PRR 1.9 | NCT01499368: 1/165 (0.6%) on Famotidine |
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.
- Chronic kidney disease-mineral and bone disorder — n=241, PRR 51.7
- Nephrogenic anaemia — n=880, PRR 41.5
- Hyperparathyroidism secondary — n=440, PRR 37.6
- Mast cell activation syndrome — n=189, PRR 29.8
- End stage renal disease — n=2,009, PRR 21.9
- Chronic kidney disease — n=6,660, PRR 17.0
- Infusion site discharge — n=130, PRR 14.7
- Accidental drug intake by child — n=96, PRR 11.8
- Aplastic anaemia — n=306, PRR 11.1
- Calcium deficiency — n=74, PRR 10.8
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 nausea, fatigue, diarrhoea, chronic kidney disease, dyspnoea, headache. 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" AND openfda.product_type:"HUMAN PRESCRIPTION DRUG") - PubChem CID 5702160 description ()
- 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, 1,159 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
FAMOTIDINE, 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.