Drug · FAERS side-effect profile with label screen

Phenobarbital combination (4 ingredients) side effects: what 916 FDA adverse event reports show

Phenobarbital, Hyoscyamine Sulfate, Atropine Sulfate, Scopolamine Hydrobromide · 31 reaction terms · 304 drug–reaction co-reports · data 2026-09-14

Drug class

Not stated in label

Who reports

916 reports · 57% serious · 36 with death outcome · 79% female

openFDA FAERS counts, all years, deduplication not applied

Used for

A. Sedative B. Anticonvulsant–For the treatment of generalized and partial seizures.

FDA label, Indications and Usage

What it is

DESCRIPTION The barbiturates are nonselective central nervous system (CNS) depressants that are primarily used as sedative-hypnotics. In sub-hypnotic doses, they are also used as anticonvulsants. The barbiturates and their sodium salts are subject to control under the Federal Controlled Substances Act.

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 23 strongest signals

Labeled adverse reaction 1Labeled (related wording) 2Reporting / coding artifact 4Lab value / disease marker 2Not in label — unassessed 14

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. 8 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
Cholelithiasis	28	19.6 13.6–28.2ROR 20.1 · χ² 475 / p 1e-105	19.3 EB05 13.9 · IC025 +3.3 3/3 methods agree	Not in label — unassessed	serious PRR 21.0 · ♀ 100% (drug 79%)	no trial data cached
Irritable bowel syndrome	17	18.2 11.4–29.2ROR 18.6 · χ² 260 / p 9e-59	17.7 EB05 11.3 · IC025 +2.8 3/3 methods agree	Not in label — unassessed	serious PRR 15.2	no trial data cached
Cholecystectomy	9	18.1 9.5–34.8ROR 18.3 · χ² 129 / p 3e-30	16.5 EB05 8.0 · IC025 +2.1 3/3 methods agree	Not in label — unassessed	serious PRR 19.1	no trial data cached
Gallbladder disorder	13	16.6 9.7–28.5ROR 16.9 · χ² 176 / p 2e-40	15.7 EB05 9.0 · IC025 +2.5 3/3 methods agree	Not in label — unassessed	serious PRR 18.6	no trial data cached
Economic problem	9	13.4 7.0–25.6ROR 13.5 · χ² 91 / p 7e-22	11.2 EB05 5.3 · IC025 +1.9 3/3 methods agree	Reporting / coding artifact	serious PRR 14.9	no trial data cached
Pharyngeal oedema	8	11.7 5.9–23.4ROR 11.8 · χ² 68 / p 7e-17	9.1 EB05 4.3 · IC025 +1.6 3/3 methods agree	Not in label — unassessed	serious PRR 9.8	no trial data cached
Injury	36	11.7 8.5–16.1ROR 12.1 · χ² 342 / p 1e-76	11.2 EB05 8.3 · IC025 +2.8 3/3 methods agree	Not in label — unassessed	serious PRR 14.3 · 79% consumer	no trial data cached
Anhedonia	12	10.4 5.9–18.2ROR 10.5 · χ² 93 / p 3e-22	8.6 EB05 4.9 · IC025 +1.9 3/3 methods agree	Not in label — unassessed	serious PRR 10.7	no trial data cached
Nervousness	21	9.2 6.0–14.0ROR 9.3 · χ² 145 / p 1e-33	8.2 EB05 5.4 · IC025 +2.2 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 11.9 · 80% consumer	no trial data cached
Blood triglycerides increased	7	9.0 4.3–18.9ROR 9.1 · χ² 42 / p 4e-11	6.4 EB05 3.2 · IC025 +1.3 3/3 methods agree	Lab value / disease marker	serious PRR 10.3	no trial data cached
Rotator cuff syndrome	5	8.9 3.7–21.3ROR 8.9 · χ² 28 / p 8e-8	5.7 EB05 2.5 · IC025 +0.8 3/3 methods agree	Not in label — unassessed	serious PRR 8.4	no trial data cached
Tardive dyskinesia (persistent involuntary movements)	10	8.0 4.3–14.9ROR 8.1 · χ² 55 / p 7e-14	6.3 EB05 3.5 · IC025 +1.5 3/3 methods agree	Not in label — unassessed	serious PRR 9.8	no trial data cached
Eructation (belching)	6	7.2 3.3–16.0ROR 7.3 · χ² 26 / p 1e-7	5.0 EB05 2.4 · IC025 +0.9 3/3 methods agree	Not in label — unassessed	serious n=3	no trial data cached
Pharmaceutical product complaint	8	7.0 3.5–13.9ROR 7.0 · χ² 35 / p 2e-9	5.2 EB05 2.8 · IC025 +1.2 3/3 methods agree	Not in label — unassessed	serious PRR 8.6	no trial data cached
Activities of daily living impaired	6	6.8 3.1–15.2ROR 6.9 · χ² 24 / p 4e-7	4.8 EB05 2.4 · IC025 +0.8 3/3 methods agree	Not in label — unassessed	serious PRR 7.8	no trial data cached
Extrapyramidal disorder	6	5.5 2.5–12.2ROR 5.5 · χ² 18 / p 1e-5	4.0 EB05 2.0 · IC025 +0.6 3/3 methods agree	Not in label — unassessed	serious PRR 6.2	no trial data cached
Wrong technique in drug usage process	8	5.0 2.5–9.9ROR 5.0 · χ² 22 / p 2e-6	4.0 EB05 2.2 · IC025 +0.8 3/3 methods agree	Reporting / coding artifact	serious PRR 8.4	no trial data cached
Emotional distress	26	4.9 3.4–7.2ROR 5.0 · χ² 77 / p 7e-19	4.5 EB05 3.3 · IC025 +1.5 3/3 methods agree	Not in label — unassessed	serious PRR 5.2	no trial data cached
Incorrect drug administration duration	6	4.8 2.2–10.7ROR 4.8 · χ² 15 / p 7e-5	3.7 EB05 1.9 · IC025 +0.5	Reporting / coding artifact	serious PRR 2.3	no trial data cached
Bone density decreased	6	4.3 2.0–9.6ROR 4.4 · χ² 12 / p 2e-4	3.4 EB05 1.7 · IC025 +0.4	Lab value / disease marker	serious PRR 3.7	no trial data cached
Inappropriate schedule of drug administration	13	4.1 2.4–7.1ROR 4.2 · χ² 28 / p 7e-8	3.7 EB05 2.3 · IC025 +0.9 3/3 methods agree	Reporting / coding artifact	serious PRR 6.8	no trial data cached
Injection site haemorrhage	9	2.6 1.4–5.0ROR 2.6 · χ² 7 / p 0.003	2.4 EB05 1.4 · IC025 +0.1	Labeled (related wording) related wording	serious PRR 2.2	no trial data cached
Drug withdrawal syndrome	9	2.3 1.2–4.4ROR 2.3 · χ² 6 / p 0.009	2.2 EB05 1.3 · IC025 -0.0 PRR-only: not supported by EBGM or IC	Labeled (related wording) related wording	serious PRR 1.7	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
Injury	36	11.7 8.5–16.1ROR 12.1 · χ² 342 / p 1e-76	11.2 EB05 8.3 · IC025 +2.8 3/3 methods agree	Not in label — unassessed	serious PRR 14.3 · 79% consumer	no trial data cached
Cholelithiasis	28	19.6 13.6–28.2ROR 20.1 · χ² 475 / p 1e-105	19.3 EB05 13.9 · IC025 +3.3 3/3 methods agree	Not in label — unassessed	serious PRR 21.0 · ♀ 100% (drug 79%)	no trial data cached
Emotional distress	26	4.9 3.4–7.2ROR 5.0 · χ² 77 / p 7e-19	4.5 EB05 3.3 · IC025 +1.5 3/3 methods agree	Not in label — unassessed	serious PRR 5.2	no trial data cached
Nervousness	21	9.2 6.0–14.0ROR 9.3 · χ² 145 / p 1e-33	8.2 EB05 5.4 · IC025 +2.2 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 11.9 · 80% consumer	no trial data cached
Irritable bowel syndrome	17	18.2 11.4–29.2ROR 18.6 · χ² 260 / p 9e-59	17.7 EB05 11.3 · IC025 +2.8 3/3 methods agree	Not in label — unassessed	serious PRR 15.2	no trial data cached
Inappropriate schedule of drug administration	13	4.1 2.4–7.1ROR 4.2 · χ² 28 / p 7e-8	3.7 EB05 2.3 · IC025 +0.9 3/3 methods agree	Reporting / coding artifact	serious PRR 6.8	no trial data cached
Gallbladder disorder	13	16.6 9.7–28.5ROR 16.9 · χ² 176 / p 2e-40	15.7 EB05 9.0 · IC025 +2.5 3/3 methods agree	Not in label — unassessed	serious PRR 18.6	no trial data cached
Anhedonia	12	10.4 5.9–18.2ROR 10.5 · χ² 93 / p 3e-22	8.6 EB05 4.9 · IC025 +1.9 3/3 methods agree	Not in label — unassessed	serious PRR 10.7	no trial data cached
Tardive dyskinesia (persistent involuntary movements)	10	8.0 4.3–14.9ROR 8.1 · χ² 55 / p 7e-14	6.3 EB05 3.5 · IC025 +1.5 3/3 methods agree	Not in label — unassessed	serious PRR 9.8	no trial data cached
Drug withdrawal syndrome	9	2.3 1.2–4.4ROR 2.3 · χ² 6 / p 0.009	2.2 EB05 1.3 · IC025 -0.0 PRR-only: not supported by EBGM or IC	Labeled (related wording) related wording	serious PRR 1.7	no trial data cached
Injection site haemorrhage	9	2.6 1.4–5.0ROR 2.6 · χ² 7 / p 0.003	2.4 EB05 1.4 · IC025 +0.1	Labeled (related wording) related wording	serious PRR 2.2	no trial data cached
Economic problem	9	13.4 7.0–25.6ROR 13.5 · χ² 91 / p 7e-22	11.2 EB05 5.3 · IC025 +1.9 3/3 methods agree	Reporting / coding artifact	serious PRR 14.9	no trial data cached
Cholecystectomy	9	18.1 9.5–34.8ROR 18.3 · χ² 129 / p 3e-30	16.5 EB05 8.0 · IC025 +2.1 3/3 methods agree	Not in label — unassessed	serious PRR 19.1	no trial data cached
Wrong technique in drug usage process	8	5.0 2.5–9.9ROR 5.0 · χ² 22 / p 2e-6	4.0 EB05 2.2 · IC025 +0.8 3/3 methods agree	Reporting / coding artifact	serious PRR 8.4	no trial data cached
Pharmaceutical product complaint	8	7.0 3.5–13.9ROR 7.0 · χ² 35 / p 2e-9	5.2 EB05 2.8 · IC025 +1.2 3/3 methods agree	Not in label — unassessed	serious PRR 8.6	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.

Cholelithiasis — n=28, PRR 19.6
Injury — n=36, PRR 11.7
Emotional distress — n=26, PRR 4.9

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 Phenobarbital?

In FDA FAERS, the most frequently co-reported reaction terms for Phenobarbital are injury, cholelithiasis, emotional distress, nervousness, irritable bowel syndrome, gallbladder disorder. 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 Phenobarbital have an FDA boxed warning?

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

Do FAERS signals prove that Phenobarbital 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 057992c1-29a0-4229-9c30-d787cb632eac, effective 20250922; matched on openfda.generic_name.exact:"PHENOBARBITAL")
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, 31 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.