Drug · FAERS side-effect profile with label screen

Dutasteride and Tamsulosin side effects: what 1,044 FDA adverse event reports show

Dutasteride And Tamsulosin Hydrochloride · 14 reaction terms · 135 drug–reaction co-reports · data 2026-09-14

Drug class

5-alpha Reductase Inhibitor

FDA label (Established Pharmacologic Class) of the closest related product

Label matched

Dutasteride (Dutasteride)

closest FDA label found for this product string; brand list suppressed because the label is a related product, not an exact match

Who reports

1,044 reports · 39% serious · 58 with death outcome · 1% female

openFDA FAERS counts, all years, deduplication not applied

Used for

Dutasteride capsules is a 5 alpha-reductase inhibitor indicated for the treatment of symptomatic benign prostatic hyperplasia (BPH) in men with an enlarged prostate to: ( 1.1 ) improve symptoms, reduce the risk of acute urinary retention, and reduce the risk of the need for BPH-related surgery.

FDA label, Indications and Usage

What it is

Dutasteride capsules are a synthetic 4-azasteroid compound that is a selective inhibitor of both the type 1 and type 2 isoforms of steroid 5 alpha-reductase, an intracellular enzyme that converts testosterone to DHT.

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 10 strongest signals

Labeled adverse reaction 4Likely indication confounding 1Reporting / coding artifact 1Lab value / disease marker 1Not in label — unassessed 3

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.
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. 4 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
Nocturia (night-time urination)	17	28.2 17.6–45.3ROR 28.7 · χ² 419 / p 2e-93	27.4 EB05 18.1 · IC025 +3.2 3/3 methods agree	Not in label — unassessed	serious PRR 12.7	no trial data cached
Erectile dysfunction	30	23.4 16.5–33.3ROR 24.1 · χ² 622 / p 2e-137	23.1 EB05 16.9 · IC025 +3.5 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 5.0 · 79% consumer	no trial data cached
Libido decreased (lower sex drive)	13	21.1 12.3–36.2ROR 21.3 · χ² 229 / p 5e-52	20.3 EB05 12.3 · IC025 +2.7 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 4.3	no trial data cached
Hypomagnesaemia	9	13.0 6.8–25.0ROR 13.1 · χ² 88 / p 3e-21	10.8 EB05 5.2 · IC025 +1.9 3/3 methods agree	Not in label — unassessed	serious PRR 20.0	no trial data cached
Prostatic specific antigen increased	8	11.6 5.8–23.1ROR 11.7 · χ² 67 / p 1e-16	9.0 EB05 4.2 · IC025 +1.6 3/3 methods agree	Lab value / disease marker	serious PRR 3.5	no trial data cached
Breast pain	6	11.3 5.1–25.1ROR 11.4 · χ² 47 / p 4e-12	7.8 EB05 3.4 · IC025 +1.2 3/3 methods agree	Labeled adverse reaction exact term	serious n=2	no trial data cached
Gynaecomastia (male breast enlargement)	14	9.0 5.3–15.1ROR 9.1 · χ² 92 / p 5e-22	7.5 EB05 4.6 · IC025 +1.9 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 6.2	no trial data cached
Internal haemorrhage	5	8.8 3.7–21.0ROR 8.8 · χ² 27 / p 1e-7	5.6 EB05 2.5 · IC025 +0.8 3/3 methods agree	Not in label — unassessed	serious PRR 13.3	no trial data cached
Drug administration error	7	4.5 2.2–9.5ROR 4.5 · χ² 16 / p 3e-5	3.6 EB05 1.9 · IC025 +0.6	Reporting / coding artifact	–	no trial data cached
Prostate cancer	10	2.5 1.3–4.6ROR 2.5 · χ² 7 / p 0.003	2.3 EB05 1.4 · IC025 +0.1	Likely indication confounding term in indications; also in warnings	serious PRR 3.7	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
Erectile dysfunction	30	23.4 16.5–33.3ROR 24.1 · χ² 622 / p 2e-137	23.1 EB05 16.9 · IC025 +3.5 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 5.0 · 79% consumer	no trial data cached
Nocturia (night-time urination)	17	28.2 17.6–45.3ROR 28.7 · χ² 419 / p 2e-93	27.4 EB05 18.1 · IC025 +3.2 3/3 methods agree	Not in label — unassessed	serious PRR 12.7	no trial data cached
Gynaecomastia (male breast enlargement)	14	9.0 5.3–15.1ROR 9.1 · χ² 92 / p 5e-22	7.5 EB05 4.6 · IC025 +1.9 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 6.2	no trial data cached
Libido decreased (lower sex drive)	13	21.1 12.3–36.2ROR 21.3 · χ² 229 / p 5e-52	20.3 EB05 12.3 · IC025 +2.7 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 4.3	no trial data cached
Prostate cancer	10	2.5 1.3–4.6ROR 2.5 · χ² 7 / p 0.003	2.3 EB05 1.4 · IC025 +0.1	Likely indication confounding term in indications; also in warnings	serious PRR 3.7	no trial data cached
Hypomagnesaemia	9	13.0 6.8–25.0ROR 13.1 · χ² 88 / p 3e-21	10.8 EB05 5.2 · IC025 +1.9 3/3 methods agree	Not in label — unassessed	serious PRR 20.0	no trial data cached
Prostatic specific antigen increased	8	11.6 5.8–23.1ROR 11.7 · χ² 67 / p 1e-16	9.0 EB05 4.2 · IC025 +1.6 3/3 methods agree	Lab value / disease marker	serious PRR 3.5	no trial data cached
Drug administration error	7	4.5 2.2–9.5ROR 4.5 · χ² 16 / p 3e-5	3.6 EB05 1.9 · IC025 +0.6	Reporting / coding artifact	–	no trial data cached
Breast pain	6	11.3 5.1–25.1ROR 11.4 · χ² 47 / p 4e-12	7.8 EB05 3.4 · IC025 +1.2 3/3 methods agree	Labeled adverse reaction exact term	serious n=2	no trial data cached
Bladder cancer	5	1.7 0.7–4.0ROR 1.7 · χ² 1 / p 0.186	1.6 EB05 0.8 · IC025 -0.9 PRR-only: not supported by EBGM or IC	Not in label — unassessed	serious PRR 2.5	no trial data cached
Internal haemorrhage	5	8.8 3.7–21.0ROR 8.8 · χ² 27 / p 1e-7	5.6 EB05 2.5 · IC025 +0.8 3/3 methods agree	Not in label — unassessed	serious PRR 13.3	no trial data cached
Wrong technique in drug usage process	4	2.2 0.8–5.8ROR 2.2 · χ² 2 / p 0.109	2.0 EB05 0.9 · IC025 -0.8 PRR-only: not supported by EBGM or IC	Reporting / coding artifact	serious PRR 2.7	no trial data cached
Sexual dysfunction	4	6.9 2.6–18.3ROR 6.9 · χ² 15 / p 6e-5	4.3 EB05 1.8 · IC025 +0.3	Labeled adverse reaction exact term	serious PRR 3.8	no trial data cached
Parkinsonism	3	6.2 2.0–19.1ROR 6.2 · χ² 8 / p 0.002	3.6 EB05 1.4 · IC025 -0.2 PRR-only: not supported by EBGM or IC	Not in label — unassessed	serious PRR 10.6	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 Dutasteride and Tamsulosin?

In FDA FAERS, the most frequently co-reported reaction terms for Dutasteride and Tamsulosin are erectile dysfunction, nocturia, gynaecomastia, libido decreased, prostate cancer, hypomagnesaemia. 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 Dutasteride and Tamsulosin have an FDA boxed warning?

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

Do FAERS signals prove that Dutasteride and Tamsulosin 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 2ad309b1-4497-8b9b-e063-6394a90aa9b4, effective 20250103; matched on openfda.generic_name.exact:"DUTASTERIDE")
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, 14 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.