Methyltestosterone side effects: what 148 FDA adverse event reports show

Methyltestosterone · Methitest · 9 reaction terms · 82 drug–reaction co-reports · data 2026-09-14

Drug class

Androgen

FDA label (Established Pharmacologic Class) · compare the class

Brand names

Methitest

openFDA label

Who reports

148 reports · 76% serious · 15 with death outcome · 64% female

openFDA FAERS counts, all years, deduplication not applied

Used for

1. Males Androgens are indicated for replacement therapy in conditions associated with a deficiency or absence of endogenous testosterone: Primary hypogonadism (congenita or acquired) — Testicular failure due to cryptohidism, bilateral torsion, orchitis, vanishing testis syndrome, or orchidectomy.

FDA label, Indications and Usage

What it is

DESCRIPTION METHITEST™ (methyltestosterone) tablets, USP contain methyltestosterone USP, a synthetic androgen. Androgens are steroids that develop and maintain primary and secondary male sex characteristics. METHITEST™ (methyltestosterone) tablets, USP are to be taken orally.

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 8 strongest signals

Reporting / coding artifact 3Not in label — unassessed 5

What the badges mean

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. 1 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
Temperature intolerance	11	152.8 86.5–269.9ROR 165.0 · χ² 1,510 / p <1e-300	121.1 EB05 72.2 · IC025 +3.3 3/3 methods agree	Not in label — unassessed	serious n=11	no trial data cached
Cardiomegaly	11	125.7 71.2–222.1ROR 135.7 · χ² 1,239 / p 1e-271	103.6 EB05 61.7 · IC025 +3.3 3/3 methods agree	Not in label — unassessed	serious PRR 98.1	no trial data cached
Brain oedema	11	123.5 69.9–218.2ROR 133.4 · χ² 1,217 / p 7e-267	102.1 EB05 60.8 · IC025 +3.3 3/3 methods agree	Not in label — unassessed	serious PRR 94.8	no trial data cached
Musculoskeletal discomfort	11	90.6 51.3–160.1ROR 97.8 · χ² 888 / p 2e-195	78.7 EB05 46.9 · IC025 +3.2 3/3 methods agree	Not in label — unassessed	serious PRR 117.9	no trial data cached
Product prescribing error	11	65.9 37.3–116.3ROR 71.1 · χ² 640 / p 2e-141	59.4 EB05 35.4 · IC025 +3.1 3/3 methods agree	Reporting / coding artifact	serious PRR 104.6	no trial data cached
Oral discomfort	6	61.1 27.9–133.8ROR 63.6 · χ² 297 / p 7e-67	51.6 EB05 25.3 · IC025 +2.0 3/3 methods agree	Not in label — unassessed	serious n=6	no trial data cached
Drug level increased	7	59.9 29.1–123.4ROR 62.8 · χ² 349 / p 4e-78	51.9 EB05 27.0 · IC025 +2.3 3/3 methods agree	Reporting / coding artifact	serious PRR 50.4	no trial data cached
Drug abuse	11	18.6 10.6–32.9ROR 20.0 · χ² 167 / p 2e-38	17.5 EB05 9.6 · IC025 +2.4 3/3 methods agree	Reporting / coding artifact	serious PRR 13.0	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
Drug abuse	11	18.6 10.6–32.9ROR 20.0 · χ² 167 / p 2e-38	17.5 EB05 9.6 · IC025 +2.4 3/3 methods agree	Reporting / coding artifact	serious PRR 13.0	no trial data cached
Product prescribing error	11	65.9 37.3–116.3ROR 71.1 · χ² 640 / p 2e-141	59.4 EB05 35.4 · IC025 +3.1 3/3 methods agree	Reporting / coding artifact	serious PRR 104.6	no trial data cached
Musculoskeletal discomfort	11	90.6 51.3–160.1ROR 97.8 · χ² 888 / p 2e-195	78.7 EB05 46.9 · IC025 +3.2 3/3 methods agree	Not in label — unassessed	serious PRR 117.9	no trial data cached
Brain oedema	11	123.5 69.9–218.2ROR 133.4 · χ² 1,217 / p 7e-267	102.1 EB05 60.8 · IC025 +3.3 3/3 methods agree	Not in label — unassessed	serious PRR 94.8	no trial data cached
Cardiomegaly	11	125.7 71.2–222.1ROR 135.7 · χ² 1,239 / p 1e-271	103.6 EB05 61.7 · IC025 +3.3 3/3 methods agree	Not in label — unassessed	serious PRR 98.1	no trial data cached
Temperature intolerance	11	152.8 86.5–269.9ROR 165.0 · χ² 1,510 / p <1e-300	121.1 EB05 72.2 · IC025 +3.3 3/3 methods agree	Not in label — unassessed	serious n=11	no trial data cached
Drug level increased	7	59.9 29.1–123.4ROR 62.8 · χ² 349 / p 4e-78	51.9 EB05 27.0 · IC025 +2.3 3/3 methods agree	Reporting / coding artifact	serious PRR 50.4	no trial data cached
Oral discomfort	6	61.1 27.9–133.8ROR 63.6 · χ² 297 / p 7e-67	51.6 EB05 25.3 · IC025 +2.0 3/3 methods agree	Not in label — unassessed	serious n=6	no trial data cached
Product adhesion issue	3	12.0 3.9–36.7ROR 12.2 · χ² 20 / p 3e-6	6.1 EB05 2.0 · IC025 +0.2	Reporting / coding artifact	–	no trial data cached

Unlabeled candidate signals

Every screened signal with n ≥ 20 was either labeled, an indication term, or an artifact pattern — no unlabeled candidate stood out in the top signals.

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 Methyltestosterone?

In FDA FAERS, the most frequently co-reported reaction terms for Methyltestosterone are musculoskeletal discomfort, brain oedema, cardiomegaly, temperature intolerance, oral discomfort. 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 Methyltestosterone have an FDA boxed warning?

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

Do FAERS signals prove that Methyltestosterone 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 77bb4ef4-c10e-4acc-8225-651d003f4561, effective 20250531; matched on openfda.generic_name.exact:"METHYLTESTOSTERONE")
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, 9 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.