Drug · FAERS side-effect profile with label screen
Atropine side effects: what 2,485 FDA adverse event reports show
Drug class
Anticholinergic, Cholinergic Muscarinic Antagonist
FDA label (Established Pharmacologic Class) · compare the class
Brand names
Atropen Auto-Injector
openFDA label
Who reports
2,485 reports · 84% serious · 386 with death outcome · 50% female
openFDA FAERS counts, all years, deduplication not applied
Used for
ATROPEN is indicated for the treatment of poisoning by susceptible organophosphorus nerve agents having cholinesterase activity as well as organophosphorus or carbamate insecticides in adult and pediatric patients. ATROPEN is a cholinergic muscarinic a.
FDA label, Indications and Usage
What it is
Each prefilled ATROPEN single-dose autoinjector provides an intramuscular dose of atropine, a cholinergic muscarinic antagonist in a self-contained unit, designed for self- or caregiver-administration.
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 adverse reaction 7Labeled (related wording) 2Reporting / coding artifact 2Lab value / disease marker 2Not in label — unassessed 27
What the badges mean
- Labeled adverse reaction The exact term appears in the label's warnings or adverse-reactions sections: a known, expected effect. The FAERS signal confirms the label rather than discovering anything.
- 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.
- 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 flags pairs whose reports are unusually skewed by sex or come mostly from consumers rather than clinicians. 124 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 |
|---|---|---|---|---|---|---|
| Macular degeneration | 197 | 142.0 124.0–162.5ROR 154.1 · χ² 26,987 / p <1e-300 | 137.8 EB05 122.3 · IC025 +6.5 3/3 methods agree | Not in label — unassessed | serious PRR 102.9 · ♀ 100% (drug 50%) | no trial data cached |
| Vaginal discharge | 65 | 55.0 43.2–70.0ROR 56.4 · χ² 3,371 / p <1e-300 | 53.8 EB05 43.7 · IC025 +4.9 3/3 methods agree | Not in label — unassessed | serious n=65 · ♀ 100% (drug 50%) | no trial data cached |
| Paraesthesia oral | 90 | 53.2 43.4–65.2ROR 55.2 · χ² 4,533 / p <1e-300 | 52.3 EB05 43.9 · IC025 +5.0 3/3 methods agree | Not in label — unassessed | serious PRR 64.5 · ♀ 100% (drug 50%) | no trial data cached |
| Oral candidiasis (oral thrush) | 66 | 43.1 33.9–54.7ROR 44.2 · χ² 2,657 / p <1e-300 | 42.4 EB05 34.4 · IC025 +4.6 3/3 methods agree | Not in label — unassessed | serious PRR 41.0 · ♀ 100% (drug 50%) | no trial data cached |
| Mydriasis | 39 | 25.8 18.9–35.2ROR 26.2 · χ² 902 / p 2e-198 | 25.4 EB05 19.4 · IC025 +3.8 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 20.4 | no trial data cached |
| Procedural pain | 84 | 25.7 20.8–31.8ROR 26.6 · χ² 1,968 / p <1e-300 | 25.5 EB05 21.3 · IC025 +4.1 3/3 methods agree | Not in label — unassessed | serious PRR 29.8 · ♀ 100% (drug 50%) | no trial data cached |
| Frequent bowel movements | 70 | 22.0 17.5–27.8ROR 22.6 · χ² 1,382 / p <1e-300 | 21.9 EB05 17.9 · IC025 +3.9 3/3 methods agree | Not in label — unassessed | serious PRR 23.2 · ♀ 97% (drug 50%) | no trial data cached |
| Colitis | 73 | 16.4 13.1–20.6ROR 16.9 · χ² 1,040 / p 2e-228 | 16.3 EB05 13.4 · IC025 +3.5 3/3 methods agree | Not in label — unassessed | serious PRR 12.0 · ♀ 94% (drug 50%) | no trial data cached |
| Rectal haemorrhage | 81 | 15.9 12.8–19.7ROR 16.4 · χ² 1,116 / p 6e-245 | 15.8 EB05 13.1 · IC025 +3.5 3/3 methods agree | Not in label — unassessed | serious PRR 11.6 · ♀ 93% (drug 50%) | no trial data cached |
| Ventricular tachycardia | 29 | 14.8 10.3–21.3ROR 15.0 · χ² 359 / p 2e-80 | 14.4 EB05 10.3 · IC025 +3.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 8.4 · 100% clinician | no trial data cached |
| Supraventricular tachycardia | 16 | 14.2 8.7–23.1ROR 14.2 · χ² 182 / p 7e-42 | 13.2 EB05 8.0 · IC025 +2.5 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 8.9 | no trial data cached |
| Colitis ulcerative | 67 | 12.7 10.0–16.1ROR 13.0 · χ² 711 / p 5e-157 | 12.5 EB05 10.1 · IC025 +3.1 3/3 methods agree | Not in label — unassessed | serious PRR 9.3 · ♀ 100% (drug 50%) | no trial data cached |
| Foot deformity | 16 | 12.2 7.5–19.9ROR 12.3 · χ² 153 / p 2e-35 | 11.0 EB05 6.6 · IC025 +2.3 3/3 methods agree | Not in label — unassessed | serious PRR 9.7 | no trial data cached |
| Ventricular fibrillation | 16 | 12.1 7.5–19.8ROR 12.2 · χ² 153 / p 2e-35 | 11.0 EB05 6.6 · IC025 +2.3 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 8.3 | no trial data cached |
| Disseminated intravascular coagulation | 20 | 12.0 7.7–18.5ROR 12.1 · χ² 190 / p 1e-43 | 11.1 EB05 7.1 · IC025 +2.5 3/3 methods agree | Not in label — unassessed | serious PRR 8.2 | no trial data cached |
| Retinal detachment | 13 | 12.0 6.9–20.6ROR 12.0 · χ² 120 / p 4e-28 | 10.4 EB05 5.9 · IC025 +2.1 3/3 methods agree | Not in label — unassessed | serious PRR 8.3 | no trial data cached |
| Toxic epidermal necrolysis (severe skin peeling reaction) | 21 | 11.8 7.7–18.0ROR 11.9 · χ² 196 / p 7e-45 | 10.9 EB05 7.1 · IC025 +2.5 3/3 methods agree | Not in label — unassessed | serious PRR 8.0 | no trial data cached |
| Haematochezia (blood in stool) | 76 | 11.7 9.3–14.6ROR 12.0 · χ² 731 / p 3e-161 | 11.5 EB05 9.4 · IC025 +3.1 3/3 methods agree | Not in label — unassessed | serious PRR 8.8 · ♀ 96% (drug 50%) | no trial data cached |
| Infusion related reaction (reaction during infusion) | 89 | 11.4 9.3–14.0ROR 11.8 · χ² 835 / p 7e-184 | 11.2 EB05 9.3 · IC025 +3.1 3/3 methods agree | Not in label — unassessed | serious PRR 9.8 · ♀ 94% (drug 50%) | no trial data cached |
| Therapeutic product effect incomplete | 94 | 11.2 9.2–13.7ROR 11.6 · χ² 868 / p 4e-191 | 11.1 EB05 9.3 · IC025 +3.1 3/3 methods agree | Reporting / coding artifact | serious PRR 14.3 · ♀ 96% (drug 50%) | no trial data cached |
| Body temperature decreased | 13 | 11.1 6.4–19.0ROR 11.1 · χ² 109 / p 8e-26 | 9.5 EB05 5.4 · IC025 +2.1 3/3 methods agree | Lab value / disease marker | serious PRR 7.7 | no trial data cached |
| Cardiogenic shock | 18 | 10.7 6.7–16.9ROR 10.7 · χ² 148 / p 2e-34 | 9.5 EB05 6.0 · IC025 +2.3 3/3 methods agree | Not in label — unassessed | serious PRR 7.3 | no trial data cached |
| Anaphylactic shock | 32 | 10.6 7.5–14.9ROR 10.7 · χ² 267 / p 2e-60 | 9.9 EB05 7.2 · IC025 +2.6 3/3 methods agree | Not in label — unassessed | serious PRR 7.0 · 96% clinician | no trial data cached |
| Ileus | 15 | 10.3 6.2–17.1ROR 10.4 · χ² 117 / p 2e-27 | 8.9 EB05 5.4 · IC025 +2.1 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 7.1 | no trial data cached |
| Bradycardia (slow heart rate) | 63 | 10.0 7.9–12.8ROR 10.3 · χ² 503 / p 8e-112 | 9.7 EB05 7.8 · IC025 +2.8 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 6.9 · 96% clinician | no trial data cached |
| Ankle fracture | 18 | 9.8 6.2–15.6ROR 9.9 · χ² 134 / p 3e-31 | 8.6 EB05 5.5 · IC025 +2.2 3/3 methods agree | Not in label — unassessed | serious PRR 7.6 | no trial data cached |
| Metabolic acidosis | 35 | 9.3 6.7–13.0ROR 9.5 · χ² 253 / p 3e-57 | 8.7 EB05 6.4 · IC025 +2.5 3/3 methods agree | Not in label — unassessed | serious PRR 6.2 | no trial data cached |
| Neuroleptic malignant syndrome | 13 | 9.2 5.4–15.9ROR 9.3 · χ² 87 / p 4e-21 | 7.7 EB05 4.5 · IC025 +1.9 3/3 methods agree | Not in label — unassessed | serious PRR 6.3 | no trial data cached |
| Muscle rigidity | 13 | 9.2 5.3–15.8ROR 9.2 · χ² 87 / p 6e-21 | 7.6 EB05 4.5 · IC025 +1.9 3/3 methods agree | Not in label — unassessed | serious PRR 7.1 | no trial data cached |
| Atelectasis | 10 | 8.7 4.7–16.2ROR 8.7 · χ² 61 / p 3e-15 | 6.8 EB05 3.8 · IC025 +1.6 3/3 methods agree | Not in label — unassessed | serious PRR 6.0 | no trial data cached |
| Photophobia (light sensitivity) | 19 | 8.6 5.5–13.5ROR 8.7 · χ² 120 / p 3e-28 | 7.5 EB05 4.9 · IC025 +2.1 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 7.0 | no trial data cached |
| Eye pain | 56 | 8.6 6.6–11.1ROR 8.7 · χ² 368 / p 3e-82 | 8.2 EB05 6.5 · IC025 +2.6 3/3 methods agree | Labeled (related wording) related wording | serious PRR 3.1 · 75% consumer | no trial data cached |
| Dyspepsia (indigestion) | 96 | 8.3 6.8–10.1ROR 8.6 · χ² 609 / p 1e-134 | 8.0 EB05 6.8 · IC025 +2.7 3/3 methods agree | Not in label — unassessed | serious PRR 11.2 · ♀ 89% (drug 50%) | no trial data cached |
| Delusion | 15 | 8.2 4.9–13.6ROR 8.2 · χ² 88 / p 4e-21 | 6.9 EB05 4.3 · IC025 +1.9 3/3 methods agree | Not in label — unassessed | serious PRR 6.7 | no trial data cached |
| Respiratory depression | 11 | 7.6 4.2–13.7ROR 7.6 · χ² 56 / p 3e-14 | 6.0 EB05 3.5 · IC025 +1.5 3/3 methods agree | Labeled (related wording) related wording | serious PRR 5.3 | no trial data cached |
| Foot fracture | 17 | 7.6 4.7–12.1ROR 7.6 · χ² 90 / p 1e-21 | 6.5 EB05 4.2 · IC025 +1.9 3/3 methods agree | Not in label — unassessed | serious PRR 6.1 | no trial data cached |
| Rhabdomyolysis (muscle breakdown) | 37 | 7.5 5.5–10.3ROR 7.6 · χ² 203 / p 3e-46 | 7.0 EB05 5.2 · IC025 +2.2 3/3 methods agree | Not in label — unassessed | serious PRR 5.2 · ♀ 7% (drug 50%) | no trial data cached |
| Blood calcium decreased | 10 | 7.5 4.0–13.9ROR 7.5 · χ² 50 / p 8e-13 | 5.9 EB05 3.3 · IC025 +1.4 3/3 methods agree | Lab value / disease marker | serious PRR 5.8 | no trial data cached |
| Cardiomyopathy | 13 | 7.4 4.3–12.8ROR 7.5 · χ² 66 / p 2e-16 | 6.1 EB05 3.7 · IC025 +1.6 3/3 methods agree | Not in label — unassessed | serious PRR 5.1 | no trial data cached |
| Post procedural complication | 16 | 7.0 4.3–11.5ROR 7.1 · χ² 77 / p 9e-19 | 6.0 EB05 3.9 · IC025 +1.7 3/3 methods agree | Reporting / coding artifact | serious PRR 4.2 | 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 |
|---|---|---|---|---|---|---|
| Macular degeneration | 197 | 142.0 124.0–162.5ROR 154.1 · χ² 26,987 / p <1e-300 | 137.8 EB05 122.3 · IC025 +6.5 3/3 methods agree | Not in label — unassessed | serious PRR 102.9 · ♀ 100% (drug 50%) | no trial data cached |
| Erythema (skin redness) | 108 | 4.4 3.7–5.3ROR 4.6 · χ² 288 / p 8e-65 | 4.4 EB05 3.7 · IC025 +1.8 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 6.4 · ♀ 82% (drug 50%) | no trial data cached |
| Dyspepsia (indigestion) | 96 | 8.3 6.8–10.1ROR 8.6 · χ² 609 / p 1e-134 | 8.0 EB05 6.8 · IC025 +2.7 3/3 methods agree | Not in label — unassessed | serious PRR 11.2 · ♀ 89% (drug 50%) | no trial data cached |
| Therapeutic product effect incomplete | 94 | 11.2 9.2–13.7ROR 11.6 · χ² 868 / p 4e-191 | 11.1 EB05 9.3 · IC025 +3.1 3/3 methods agree | Reporting / coding artifact | serious PRR 14.3 · ♀ 96% (drug 50%) | no trial data cached |
| Paraesthesia oral | 90 | 53.2 43.4–65.2ROR 55.2 · χ² 4,533 / p <1e-300 | 52.3 EB05 43.9 · IC025 +5.0 3/3 methods agree | Not in label — unassessed | serious PRR 64.5 · ♀ 100% (drug 50%) | no trial data cached |
| Infusion related reaction (reaction during infusion) | 89 | 11.4 9.3–14.0ROR 11.8 · χ² 835 / p 7e-184 | 11.2 EB05 9.3 · IC025 +3.1 3/3 methods agree | Not in label — unassessed | serious PRR 9.8 · ♀ 94% (drug 50%) | no trial data cached |
| Procedural pain | 84 | 25.7 20.8–31.8ROR 26.6 · χ² 1,968 / p <1e-300 | 25.5 EB05 21.3 · IC025 +4.1 3/3 methods agree | Not in label — unassessed | serious PRR 29.8 · ♀ 100% (drug 50%) | no trial data cached |
| Drug hypersensitivity | 82 | 3.6 2.9–4.4ROR 3.7 · χ² 150 / p 8e-35 | 3.5 EB05 2.9 · IC025 +1.4 3/3 methods agree | Labeled (related wording) related wording | serious PRR 1.2 | no trial data cached |
| Rectal haemorrhage | 81 | 15.9 12.8–19.7ROR 16.4 · χ² 1,116 / p 6e-245 | 15.8 EB05 13.1 · IC025 +3.5 3/3 methods agree | Not in label — unassessed | serious PRR 11.6 · ♀ 93% (drug 50%) | no trial data cached |
| Haematochezia (blood in stool) | 76 | 11.7 9.3–14.6ROR 12.0 · χ² 731 / p 3e-161 | 11.5 EB05 9.4 · IC025 +3.1 3/3 methods agree | Not in label — unassessed | serious PRR 8.8 · ♀ 96% (drug 50%) | no trial data cached |
| Colitis | 73 | 16.4 13.1–20.6ROR 16.9 · χ² 1,040 / p 2e-228 | 16.3 EB05 13.4 · IC025 +3.5 3/3 methods agree | Not in label — unassessed | serious PRR 12.0 · ♀ 94% (drug 50%) | no trial data cached |
| Toxicity to various agents | 72 | 3.6 2.9–4.6ROR 3.7 · χ² 135 / p 1e-31 | 3.6 EB05 2.9 · IC025 +1.4 3/3 methods agree | Not in label — unassessed | serious PRR 2.5 | no trial data cached |
| Frequent bowel movements | 70 | 22.0 17.5–27.8ROR 22.6 · χ² 1,382 / p <1e-300 | 21.9 EB05 17.9 · IC025 +3.9 3/3 methods agree | Not in label — unassessed | serious PRR 23.2 · ♀ 97% (drug 50%) | no trial data cached |
| Colitis ulcerative | 67 | 12.7 10.0–16.1ROR 13.0 · χ² 711 / p 5e-157 | 12.5 EB05 10.1 · IC025 +3.1 3/3 methods agree | Not in label — unassessed | serious PRR 9.3 · ♀ 100% (drug 50%) | no trial data cached |
| Oral candidiasis (oral thrush) | 66 | 43.1 33.9–54.7ROR 44.2 · χ² 2,657 / p <1e-300 | 42.4 EB05 34.4 · IC025 +4.6 3/3 methods agree | Not in label — unassessed | serious PRR 41.0 · ♀ 100% (drug 50%) | 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.
- Macular degeneration — n=197, PRR 142.0
- Vaginal discharge — n=65, PRR 55.0
- Paraesthesia oral — n=90, PRR 53.2
- Oral candidiasis — n=66, PRR 43.1
- Procedural pain — n=84, PRR 25.7
- Frequent bowel movements — n=70, PRR 22.0
- Colitis — n=73, PRR 16.4
- Rectal haemorrhage — n=81, PRR 15.9
- Colitis ulcerative — n=67, PRR 12.7
- Disseminated intravascular coagulation — n=20, PRR 12.0
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 Atropine?
In FDA FAERS, the most frequently co-reported reaction terms for Atropine are macular degeneration, erythema, dyspepsia, paraesthesia oral, infusion related reaction, procedural 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 Atropine have an FDA boxed warning?
No. The FDA label retrieved for Atropine has no boxed warning; see the label's Warnings and Precautions for the recognised risks.
Do FAERS signals prove that Atropine 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 e2d4307d-da8f-49f5-aac0-02355dd9ffb7, effective 20220915; matched on
openfda.generic_name.exact:"ATROPINE") - 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, 164 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.