Metyrapone side effects: what 977 FDA adverse event reports show

Metyrapone · Metopirone · 24 reaction terms · 386 drug–reaction co-reports · data 2026-09-14

Drug class

Adrenal Steroid Synthesis Inhibitor

FDA label (Established Pharmacologic Class)

Brand names

Metopirone

openFDA label

Who reports

977 reports · 67% serious · 120 with death outcome · 65% female

openFDA FAERS counts, all years, deduplication not applied

Used for

Metopirone is indicated, in combination with other diagnostic tests, for the diagnosis of adrenal insufficiency in adult and pediatric patients. Metopirone is indicated, in combination with other diagnostic tests, for the diagnosis of adrenal insufficiency in adult and pediatric patients. ( 1 )

FDA label, Indications and Usage

What it is

Metopirone (metyrapone capsules) is an adrenal steroid synthesis inhibitor, available as 250‑mg capsules for oral 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 15 strongest signals

Likely indication confounding 1Reporting / coding artifact 4Lab value / disease marker 1Not in label — unassessed 9

What the badges mean

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 flags pairs whose reports are unusually skewed by sex or come mostly from consumers rather than clinicians. 9 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
Adrenal insufficiency	43	77.4 57.7–103.7ROR 80.9 · χ² 3,155 / p <1e-300	74.6 EB05 57.7 · IC025 +4.9 3/3 methods agree	Likely indication confounding term in indications; also in warnings	serious PRR 67.3	no trial data cached
Pneumocystis jirovecii pneumonia	35	75.4 54.4–104.5ROR 78.2 · χ² 2,488 / p <1e-300	72.3 EB05 54.3 · IC025 +4.6 3/3 methods agree	Not in label — unassessed	serious PRR 65.0 · 97% clinician	no trial data cached
Premature delivery	26	34.9 23.9–51.1ROR 35.9 · χ² 823 / p 3e-181	34.1 EB05 24.4 · IC025 +3.8 3/3 methods agree	Not in label — unassessed	serious PRR 30.8 · ♀ 100% (drug 65%) · 100% clinician	no trial data cached
Hepatic encephalopathy	10	23.0 12.4–42.6ROR 23.2 · χ² 189 / p 3e-43	21.8 EB05 12.1 · IC025 +2.4 3/3 methods agree	Not in label — unassessed	serious PRR 19.9	no trial data cached
Premature baby	27	19.2 13.2–27.9ROR 19.7 · χ² 448 / p 9e-100	18.9 EB05 13.6 · IC025 +3.2 3/3 methods agree	Not in label — unassessed	serious PRR 16.8 · 100% clinician	no trial data cached
Hyperglycaemia (high blood sugar)	26	15.4 10.5–22.5ROR 15.8 · χ² 335 / p 3e-75	15.0 EB05 10.5 · IC025 +2.9 3/3 methods agree	Not in label — unassessed	serious PRR 14.4 · 96% clinician	no trial data cached
Metastases to bone	11	14.4 8.0–26.0ROR 14.6 · χ² 124 / p 3e-29	12.9 EB05 6.7 · IC025 +2.2 3/3 methods agree	Not in label — unassessed	serious PRR 12.6	no trial data cached
Acute respiratory distress syndrome	11	13.4 7.4–24.0ROR 13.5 · χ² 114 / p 8e-27	11.7 EB05 6.1 · IC025 +2.1 3/3 methods agree	Not in label — unassessed	serious PRR 11.5	no trial data cached
Gamma-glutamyltransferase increased	12	11.6 6.6–20.4ROR 11.7 · χ² 106 / p 3e-25	9.9 EB05 5.4 · IC025 +2.0 3/3 methods agree	Lab value / disease marker	serious PRR 10.4	no trial data cached
Hepatitis (liver inflammation)	13	10.9 6.4–18.7ROR 11.0 · χ² 107 / p 2e-25	9.3 EB05 5.3 · IC025 +2.1 3/3 methods agree	Not in label — unassessed	serious PRR 9.6	no trial data cached
Neoplasm progression	16	9.8 6.0–15.9ROR 9.9 · χ² 118 / p 1e-27	8.5 EB05 5.2 · IC025 +2.1 3/3 methods agree	Not in label — unassessed	serious PRR 11.7	no trial data cached
Exposure during pregnancy	26	9.0 6.1–13.1ROR 9.2 · χ² 177 / p 1e-40	8.2 EB05 5.7 · IC025 +2.3 3/3 methods agree	Reporting / coding artifact	serious PRR 9.4 · ♀ 100% (drug 65%) · 96% clinician	no trial data cached
Maternal exposure during pregnancy	35	8.5 6.2–11.8ROR 8.8 · χ² 226 / p 3e-51	7.9 EB05 5.9 · IC025 +2.4 3/3 methods agree	Reporting / coding artifact	serious PRR 8.3 · ♀ 91% (drug 65%) · 100% clinician	no trial data cached
Foetal exposure during pregnancy	22	5.8 3.8–8.8ROR 5.9 · χ² 83 / p 4e-20	5.2 EB05 3.6 · IC025 +1.7 3/3 methods agree	Reporting / coding artifact	serious PRR 5.1 · 100% clinician	no trial data cached
Malignant neoplasm progression	22	4.6 3.1–7.0ROR 4.7 · χ² 59 / p 6e-15	4.3 EB05 3.0 · IC025 +1.4 3/3 methods agree	Reporting / coding artifact	serious PRR 4.1	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
Adrenal insufficiency	43	77.4 57.7–103.7ROR 80.9 · χ² 3,155 / p <1e-300	74.6 EB05 57.7 · IC025 +4.9 3/3 methods agree	Likely indication confounding term in indications; also in warnings	serious PRR 67.3	no trial data cached
Maternal exposure during pregnancy	35	8.5 6.2–11.8ROR 8.8 · χ² 226 / p 3e-51	7.9 EB05 5.9 · IC025 +2.4 3/3 methods agree	Reporting / coding artifact	serious PRR 8.3 · ♀ 91% (drug 65%) · 100% clinician	no trial data cached
Pneumocystis jirovecii pneumonia	35	75.4 54.4–104.5ROR 78.2 · χ² 2,488 / p <1e-300	72.3 EB05 54.3 · IC025 +4.6 3/3 methods agree	Not in label — unassessed	serious PRR 65.0 · 97% clinician	no trial data cached
Premature baby	27	19.2 13.2–27.9ROR 19.7 · χ² 448 / p 9e-100	18.9 EB05 13.6 · IC025 +3.2 3/3 methods agree	Not in label — unassessed	serious PRR 16.8 · 100% clinician	no trial data cached
Exposure during pregnancy	26	9.0 6.1–13.1ROR 9.2 · χ² 177 / p 1e-40	8.2 EB05 5.7 · IC025 +2.3 3/3 methods agree	Reporting / coding artifact	serious PRR 9.4 · ♀ 100% (drug 65%) · 96% clinician	no trial data cached
Hyperglycaemia (high blood sugar)	26	15.4 10.5–22.5ROR 15.8 · χ² 335 / p 3e-75	15.0 EB05 10.5 · IC025 +2.9 3/3 methods agree	Not in label — unassessed	serious PRR 14.4 · 96% clinician	no trial data cached
Premature delivery	26	34.9 23.9–51.1ROR 35.9 · χ² 823 / p 3e-181	34.1 EB05 24.4 · IC025 +3.8 3/3 methods agree	Not in label — unassessed	serious PRR 30.8 · ♀ 100% (drug 65%) · 100% clinician	no trial data cached
Malignant neoplasm progression	22	4.6 3.1–7.0ROR 4.7 · χ² 59 / p 6e-15	4.3 EB05 3.0 · IC025 +1.4 3/3 methods agree	Reporting / coding artifact	serious PRR 4.1	no trial data cached
Foetal exposure during pregnancy	22	5.8 3.8–8.8ROR 5.9 · χ² 83 / p 4e-20	5.2 EB05 3.6 · IC025 +1.7 3/3 methods agree	Reporting / coding artifact	serious PRR 5.1 · 100% clinician	no trial data cached
Neoplasm progression	16	9.8 6.0–15.9ROR 9.9 · χ² 118 / p 1e-27	8.5 EB05 5.2 · IC025 +2.1 3/3 methods agree	Not in label — unassessed	serious PRR 11.7	no trial data cached
Hepatitis (liver inflammation)	13	10.9 6.4–18.7ROR 11.0 · χ² 107 / p 2e-25	9.3 EB05 5.3 · IC025 +2.1 3/3 methods agree	Not in label — unassessed	serious PRR 9.6	no trial data cached
Gamma-glutamyltransferase increased	12	11.6 6.6–20.4ROR 11.7 · χ² 106 / p 3e-25	9.9 EB05 5.4 · IC025 +2.0 3/3 methods agree	Lab value / disease marker	serious PRR 10.4	no trial data cached
Acute respiratory distress syndrome	11	13.4 7.4–24.0ROR 13.5 · χ² 114 / p 8e-27	11.7 EB05 6.1 · IC025 +2.1 3/3 methods agree	Not in label — unassessed	serious PRR 11.5	no trial data cached
Metastases to bone	11	14.4 8.0–26.0ROR 14.6 · χ² 124 / p 3e-29	12.9 EB05 6.7 · IC025 +2.2 3/3 methods agree	Not in label — unassessed	serious PRR 12.6	no trial data cached
Hepatic encephalopathy	10	23.0 12.4–42.6ROR 23.2 · χ² 189 / p 3e-43	21.8 EB05 12.1 · IC025 +2.4 3/3 methods agree	Not in label — unassessed	serious PRR 19.9	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.

Pneumocystis jirovecii pneumonia — n=35, PRR 75.4
Premature delivery — n=26, PRR 34.9
Premature baby — n=27, PRR 19.2
Hyperglycaemia — n=26, PRR 15.4

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 Metyrapone?

In FDA FAERS, the most frequently co-reported reaction terms for Metyrapone are adrenal insufficiency, pneumocystis jirovecii pneumonia, premature baby, hyperglycaemia, premature delivery, neoplasm progression. 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 Metyrapone have an FDA boxed warning?

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

Do FAERS signals prove that Metyrapone 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 4046b167-7a46-8f4a-e063-6394a90a147f, effective 20260519; matched on openfda.generic_name.exact:"METYRAPONE")
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, 24 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.