Tadalafil side effects: what 99,461 FDA adverse event reports show

Tadalafil · 1,239 reaction terms · 367,211 drug–reaction co-reports · data 2026-09-14

Drug class

Phosphodiesterase 5 Inhibitor

FDA label (Established Pharmacologic Class)

Who reports

99,461 reports · 62% serious · 11,120 with death outcome · 53% female

openFDA FAERS counts, all years, deduplication not applied

Used for

Tadalafil is a phosphodiesterase 5 (PDE5) inhibitor indicated for the treatment of: erectile dysfunction (ED) ( 1.1 ) the signs and symptoms of benign prostatic hyperplasia (BPH) ( 1.2 ) ED and the signs and symptoms of BPH (ED/BPH) ( 1.3 ) If tadalafil is used with finasteride to initiate BPH treatment, such use is recommended for up to 26 weeks ( 1.4 ).

FDA label, Indications and Usage

What it is

Tadalafil, USP is a selective inhibitor of cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase type 5 (PDE5). Tadalafil has the molecular formula C 22 H 19 N 3 O 4 representing a molecular weight of 389.41.

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 1Labeled (related wording) 7Reporting / coding artifact 4Lab value / disease marker 3Not in label — unassessed 25

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, for the 300 most-reported drugs, adjusted for age band), and flags pairs whose reports are unusually skewed by sex or come mostly from consumers. Each row also shows the PRR against the other drugs of the same FDA class, which removes most confounding by the condition being treated, and a calibrated p-value: on validation, known non-causes average an ROR of about 2, so significance is judged against that empirical null (✓ = p < 0.05 after calibration). 1,199 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
Fractional exhaled nitric oxide increased	123	530.1 379.8–739.9ROR 530.7 · calibrated p 1e-13 ✓	146.2 EB05 125.7 · IC025 +6.2 3/3 methods agree	Not in label — unassessed	serious n=123 · ♀ 0% (drug 53%)	not reported in cached trials
Malignant melanoma stage ii	75	189.2 138.3–258.8ROR 189.3 · calibrated p 2e-9 ✓	96.9 EB05 79.9 · IC025 +5.5 3/3 methods agree	Not in label — unassessed	serious n=75 · ♀ 0% (drug 53%) · 100% consumer	not reported in cached trials
Malignant melanoma stage i	97	116.0 90.5–148.7ROR 116.1 · calibrated p 6e-8 ✓	73.6 EB05 62.1 · IC025 +5.4 3/3 methods agree	Not in label — unassessed	serious n=97 · ♀ 0% (drug 53%) · 100% consumer	not reported in cached trials
Infusion site pustule	42	104.7 72.2–151.7ROR 104.7 · calibrated p 2e-7 ✓	67.8 EB05 52.3 · IC025 +4.8 3/3 methods agree	Not in label — unassessed	♀ 100% (drug 53%) · 100% consumer	not reported in cached trials
Malignant melanoma stage iii	60	88.0 65.1–119.1ROR 88.1 · calibrated p 5e-7 ✓	60.9 EB05 49.0 · IC025 +4.9 3/3 methods agree	Not in label — unassessed	serious n=60 · ♀ 0% (drug 53%) · 100% consumer	not reported in cached trials
Device wireless communication issue	73	86.8 66.0–114.1ROR 86.9 · calibrated p 5e-7 ✓	60.5 EB05 49.7 · IC025 +5.1 3/3 methods agree	Reporting / coding artifact	♀ 100% (drug 53%) · 100% consumer	not reported in cached trials
Catheter site vesicles	55	84.9 62.0–116.2ROR 85.0 · calibrated p 7e-7 ✓	59.3 EB05 47.3 · IC025 +4.9 3/3 methods agree	Not in label — unassessed	serious n=45 · ♀ 100% (drug 53%) · 100% clinician	not reported in cached trials
Catheter site pruritus	245	81.9 70.6–94.9ROR 82.1 · calibrated p 5e-7 ✓	58.7 EB05 52.8 · IC025 +5.5 3/3 methods agree	Not in label — unassessed	serious n=199 · ♀ 85% (drug 53%)	not reported in cached trials
Malignant melanoma stage iv	79	80.9 62.4–104.9ROR 81.0 · calibrated p 8e-7 ✓	57.7 EB05 47.8 · IC025 +5.1 3/3 methods agree	Not in label — unassessed	serious n=78 · ♀ 0% (drug 53%) · 100% consumer	not reported in cached trials
Catheter site rash	117	73.8 59.8–91.1ROR 73.9 · calibrated p 1e-6 ✓	54.2 EB05 46.4 · IC025 +5.2 3/3 methods agree	Not in label — unassessed	serious n=97 · ♀ 81% (drug 53%)	not reported in cached trials
Catheter management	232	72.8 62.7–84.6ROR 73.0 · calibrated p 1e-6 ✓	53.9 EB05 48.3 · IC025 +5.4 3/3 methods agree	Reporting / coding artifact	serious n=222 · ♀ 80% (drug 53%) · 100% clinician	NCT00384930: 1/212 (0.5%) control (serious AE)
Device maintenance issue	142	70.8 58.5–85.6ROR 70.9 · calibrated p 2e-6 ✓	52.6 EB05 45.8 · IC025 +5.2 3/3 methods agree	Reporting / coding artifact	serious n=45 · ♀ 76% (drug 53%) · 100% consumer	not reported in cached trials
Catheter site irritation	78	68.1 52.7–87.9ROR 68.1 · calibrated p 3e-6 ✓	50.9 EB05 42.1 · IC025 +4.9 3/3 methods agree	Not in label — unassessed	serious n=64 · ♀ 100% (drug 53%)	not reported in cached trials
Libido disorder	311	66.1 58.1–75.0ROR 66.3 · calibrated p 2e-6 ✓	50.2 EB05 45.7 · IC025 +5.4 3/3 methods agree	Not in label — unassessed	♀ 0% (drug 53%) · 100% consumer	not reported in cached trials
Transplant evaluation	115	61.2 49.7–75.3ROR 61.2 · calibrated p 5e-6 ✓	47.1 EB05 40.3 · IC025 +5.0 3/3 methods agree	Not in label — unassessed	serious n=114	not reported in cached trials
Malignant melanoma in situ	278	59.5 52.1–68.0ROR 59.7 · calibrated p 5e-6 ✓	46.3 EB05 41.9 · IC025 +5.2 3/3 methods agree	Not in label — unassessed	serious n=278 · ♀ 0% (drug 53%) · 72% consumer	not reported in cached trials
Pulmonary hypertensive crisis	58	58.5 43.7–78.3ROR 58.6 · calibrated p 7e-6 ✓	45.2 EB05 36.3 · IC025 +4.6 3/3 methods agree	Not in label — unassessed	serious n=58 · ♀ 100% (drug 53%) · 100% clinician	not reported in cached trials
Infusion site infection	489	57.9 52.4–64.0ROR 58.2 · calibrated p 5e-6 ✓	45.4 EB05 42.1 · IC025 +5.3 3/3 methods agree	Labeled (related wording) related wording	serious n=240 · ♀ 78% (drug 53%)	NCT00384930: 1/212 (0.5%) on Tadalafil
Catheter site discharge	236	57.4 49.7–66.3ROR 57.6 · calibrated p 6e-6 ✓	45.0 EB05 40.4 · IC025 +5.2 3/3 methods agree	Not in label — unassessed	serious n=190 · ♀ 82% (drug 53%)	not reported in cached trials
Walking distance test abnormal	82	56.7 44.4–72.4ROR 56.8 · calibrated p 8e-6 ✓	44.3 EB05 36.8 · IC025 +4.8 3/3 methods agree	Reporting / coding artifact	serious n=46	not reported in cached trials
Congenital hiatus hernia	44	52.0 37.4–72.4ROR 52.0 · calibrated p 2e-5 ✓	41.1 EB05 31.9 · IC025 +4.3 3/3 methods agree	Not in label — unassessed	serious n=44 · ♀ 0% (drug 53%) · 100% clinician	not reported in cached trials
Pulmonary arterial hypertension	2,878	51.8 49.7–53.9ROR 53.3 · calibrated p 9e-6 ✓	41.6 EB05 40.3 · IC025 +5.3 3/3 methods agree	Not in label — unassessed	age-adj. PRR 47.5 · serious PRR 37.8	not reported in cached trials
Infusion site discharge	318	48.0 42.5–54.2ROR 48.2 · calibrated p 2e-5 ✓	39.1 EB05 35.6 · IC025 +5.0 3/3 methods agree	Not in label — unassessed	serious n=94 · ♀ 79% (drug 53%) · 74% consumer	not reported in cached trials
Cardiac failure high output	44	47.7 34.3–66.1ROR 47.7 · calibrated p 3e-5 ✓	38.3 EB05 29.7 · IC025 +4.3 3/3 methods agree	Labeled (related wording) related wording	serious n=44 · ♀ 100% (drug 53%) · 100% clinician	not reported in cached trials
Catheter site erythema	384	47.2 42.3–52.7ROR 47.4 · calibrated p 2e-5 ✓	38.5 EB05 35.4 · IC025 +5.0 3/3 methods agree	Not in label — unassessed	serious n=313 · ♀ 81% (drug 53%)	not reported in cached trials
Pulmonary arterial pressure increased	293	45.9 40.4–52.1ROR 46.0 · calibrated p 2e-5 ✓	37.7 EB05 34.2 · IC025 +5.0 3/3 methods agree	Lab value / disease marker	serious n=231 · ♀ 81% (drug 53%)	not reported in cached trials
Pulmonary arterial pressure abnormal	51	45.3 33.4–61.3ROR 45.3 · calibrated p 4e-5 ✓	36.9 EB05 29.1 · IC025 +4.3 3/3 methods agree	Lab value / disease marker	serious n=40 · ♀ 100% (drug 53%) · 100% clinician	not reported in cached trials
Pulmonary veno-occlusive disease	114	41.2 33.7–50.3ROR 41.2 · calibrated p 5e-5 ✓	34.3 EB05 29.3 · IC025 +4.6 3/3 methods agree	Not in label — unassessed	serious n=113	not reported in cached trials
Right ventricular failure	1,100	38.8 36.3–41.3ROR 39.2 · calibrated p 6e-5 ✓	32.8 EB05 31.2 · IC025 +4.9 3/3 methods agree	Labeled (related wording) related wording	serious PRR 30.2	not reported in cached trials
Spontaneous penile erection	96	38.3 30.8–47.7ROR 38.4 · calibrated p 8e-5 ✓	32.3 EB05 27.2 · IC025 +4.5 3/3 methods agree	Labeled adverse reaction exact term	♀ 0% (drug 53%) · 100% consumer	not reported in cached trials
Infusion site warmth	184	37.9 32.4–44.4ROR 38.0 · calibrated p 8e-5 ✓	32.1 EB05 28.4 · IC025 +4.6 3/3 methods agree	Not in label — unassessed	serious n=59 · ♀ 84% (drug 53%) · 73% consumer	not reported in cached trials
Infusion site irritation	186	37.0 31.6–43.2ROR 37.0 · calibrated p 9e-5 ✓	31.4 EB05 27.8 · IC025 +4.6 3/3 methods agree	Not in label — unassessed	serious n=63 · ♀ 78% (drug 53%) · 79% consumer	NCT00384930: 1/209 (0.5%) on Tadalafil
Oxygen consumption increased	353	36.9 33.0–41.4ROR 37.1 · calibrated p 8e-5 ✓	31.4 EB05 28.8 · IC025 +4.7 3/3 methods agree	Lab value / disease marker	serious n=251 · ♀ 78% (drug 53%)	not reported in cached trials
Infusion site oedema	121	35.9 29.6–43.6ROR 36.0 · calibrated p 1e-4 ✓	30.6 EB05 26.3 · IC025 +4.5 3/3 methods agree	Labeled (related wording) related wording	serious n=35 · ♀ 79% (drug 53%) · 74% consumer	NCT00384930: 1/216 (0.5%) on Tadalafil
Infusion site induration	207	35.8 30.9–41.5ROR 35.9 · calibrated p 1e-4 ✓	30.6 EB05 27.3 · IC025 +4.6 3/3 methods agree	Not in label — unassessed	serious n=65 · ♀ 81% (drug 53%) · 79% consumer	not reported in cached trials
Infusion site haemorrhage	463	35.0 31.7–38.6ROR 35.2 · calibrated p 1e-4 ✓	30.1 EB05 27.8 · IC025 +4.7 3/3 methods agree	Labeled (related wording) related wording	serious n=145 · ♀ 77% (drug 53%) · 78% consumer	NCT00384930: 1/212 (0.5%) on Tadalafil
Infusion site pain	1,802	34.5 32.8–36.3ROR 35.1 · calibrated p 1e-4 ✓	29.7 EB05 28.6 · IC025 +4.8 3/3 methods agree	Labeled (related wording) related wording	age-adj. PRR 28.7 · serious n=659 · ♀ 79% (drug 53%) · 72% consumer	NCT00384930: 1/209 (0.5%) on Tadalafil (serious AE)
Vascular device occlusion	47	34.1 25.1–46.4ROR 34.1 · calibrated p 2e-4 ✓	29.1 EB05 22.8 · IC025 +4.0 3/3 methods agree	Labeled (related wording) related wording	serious n=46 · ♀ 100% (drug 53%) · 100% consumer	not reported in cached trials
Catheter site swelling	127	33.7 27.9–40.6ROR 33.7 · calibrated p 2e-4 ✓	29.0 EB05 25.0 · IC025 +4.4 3/3 methods agree	Not in label — unassessed	serious n=104 · ♀ 100% (drug 53%)	not reported in cached trials
Infusion site vesicles	72	33.5 26.2–43.0ROR 33.6 · calibrated p 2e-4 ✓	28.8 EB05 23.6 · IC025 +4.2 3/3 methods agree	Not in label — unassessed	♀ 73% (drug 53%) · 100% consumer	not reported in cached trials

Clinical concept groups

MedDRA splits one clinical problem across several terms (e.g. "neutropenia", "neutrophil count decreased", "agranulocytosis"), which dilutes term-level signals. These rows count reports with any term in a concept group (an exact union, not a sum), compared with all other drugs. Groups are hand-built and listed in the methods.

Concept	Reports	PRR 95% CI	Reading
Heart failure	2,681	3.23.1–3.3	signal
Serious infection	7,059	1.91.9–2.0	raised
Arrhythmia / qt	1,631	1.81.7–1.9	raised
Anaemia	2,295	1.61.6–1.7	raised
Gi bleeding	1,273	1.51.4–1.6	raised
Fall / fracture	2,436	1.41.3–1.4	raised
Interstitial lung disease	599	1.31.2–1.4	raised
Depression	1,661	1.21.2–1.3	raised
Kidney injury	2,344	1.11.0–1.1	raised
Venous thromboembolism	962	0.90.9–1.0	lower than other drugs
Stroke	1,056	0.90.8–0.9	lower than other drugs
Myocardial infarction	823	0.80.8–0.9	lower than other drugs
Thrombocytopenia	830	0.80.7–0.8	lower than other drugs
Pancreatitis	286	0.70.7–0.8	lower than other drugs
Hyponatraemia	284	0.70.7–0.8	lower than other drugs
Hyperglycaemia / diabetes	1,147	0.70.7–0.7	lower than other drugs

Trial evidence (ClinicalTrials.gov)

✓ Trial adverse-event data found on ClinicalTrials.gov

Largest completed trials with posted results that list Tadalafil as a study intervention. The right-hand column of the signal table shows whether each FAERS term was also recorded in these trials, with a real denominator (6 of 40 signal terms matched).

NCT00384930 — Study of Tadalafil Once-a Day for 12 Weeks in Men With Signs and Symptoms of Benign Prostatic Hyperplasia (N=1058, PHASE2, PHASE3; 215 AE terms posted; arms: Placebo; 2.5 mg Tadalafil; 5 mg Tadalafil; 10 mg Tadalafil)
NCT01937871 — A Study of Tadalafil in Men With Benign Prostatic Hyperplasia (BPH) and Erectile Dysfunction (ED) (N=909, PHASE3; 133 AE terms posted; arms: Placebo; 5 mg Tadalafil; 0.2 mg Tamsulosin)

Caveats: trial populations, doses and follow-up differ from the reporting population; AE terms are sponsor-coded and matched here by wording; absence from a trial list means the term was not reported above the sponsor's frequency threshold, not that it cannot occur.

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
Dyspnoea (shortness of breath)	11,993	4.5 4.5–4.6ROR 5.0 · calibrated p 0.231	4.5 EB05 4.4 · IC025 +2.1 3/3 methods agree	Labeled adverse reaction exact term	age-adj. PRR 4.2 · serious PRR 4.3	NCT00384930: 1/209 (0.5%) on Tadalafil
Headache	11,025	3.8 3.7–3.8ROR 4.1 · calibrated p 0.359	3.7 EB05 3.7 · IC025 +1.9 3/3 methods agree	Labeled adverse reaction exact term	age-adj. PRR 3.5 · serious PRR 3.6	NCT00384930: 7/209 (3.3%) on Tadalafil; 6/212 (2.8%) control
Diarrhoea (diarrhea)	8,044	2.7 2.6–2.7ROR 2.8 · calibrated p 0.695	2.6 EB05 2.6 · IC025 +1.4 3/3 methods agree	Labeled adverse reaction exact term	age-adj. PRR 2.4 · serious PRR 2.6	NCT00384930: 5/209 (2.4%) on Tadalafil; 3/212 (1.4%) control
Nausea	6,720	1.8 1.8–1.8ROR 1.9 · calibrated p 0.865	1.8 EB05 1.8 · IC025 +0.8	Labeled adverse reaction exact term	age-adj. PRR 1.7 · serious PRR 1.9 · ♀ 74% (drug 53%)	NCT00384930: 3/212 (1.4%) on Tadalafil; 1/212 (0.5%) control
Fatigue (tiredness)	6,092	1.7 1.6–1.7ROR 1.7 · calibrated p 0.769	1.7 EB05 1.6 · IC025 +0.7	Labeled adverse reaction exact term	age-adj. PRR 1.5 · serious PRR 1.7	NCT00384930: 1/216 (0.5%) on Tadalafil; 1/212 (0.5%) control
Death	6,009	1.5 1.4–1.5ROR 1.5 · calibrated p 0.644	1.5 EB05 1.4 · IC025 +0.5	Outcome field, not a reaction	age-adj. PRR 1.9 · serious PRR 1.3	not reported in cached trials
Drug ineffective (drug did not work)	5,572	0.9 0.9–0.9ROR 0.9 · calibrated p 0.233	0.9 EB05 0.9 · IC025 -0.2 PRR-only: not supported by EBGM or IC	Reporting / coding artifact	age-adj. PRR 0.9 · serious PRR 0.6 · ♀ 13% (drug 53%) · 78% consumer	not reported in cached trials
Dizziness	5,346	2.3 2.2–2.3ROR 2.3 · calibrated p 0.880	2.3 EB05 2.2 · IC025 +1.1 3/3 methods agree	Labeled adverse reaction exact term	age-adj. PRR 2.1 · serious PRR 2.2	NCT00384930: 3/209 (1.4%) on Tadalafil; 1/212 (0.5%) control
Cough	4,446	3.4 3.3–3.5ROR 3.5 · calibrated p 0.485	3.3 EB05 3.3 · IC025 +1.7 3/3 methods agree	Labeled adverse reaction exact term	age-adj. PRR 2.8 · serious PRR 3.0	NCT00384930: 2/216 (0.9%) on Tadalafil; 1/212 (0.5%) control
Pneumonia (lung infection)	4,317	2.8 2.8–2.9ROR 2.9 · calibrated p 0.652	2.8 EB05 2.7 · IC025 +1.4 3/3 methods agree	Labeled (related wording) related wording	age-adj. PRR 2.7 · serious PRR 2.6	NCT00384930: 1/212 (0.5%) on Tadalafil
Malaise (feeling unwell)	3,812	1.8 1.8–1.9ROR 1.9 · calibrated p 0.869	1.8 EB05 1.8 · IC025 +0.8	Not in label — unassessed	age-adj. PRR 1.9 · serious PRR 1.9 · ♀ 73% (drug 53%)	not reported in cached trials
Vomiting	3,540	1.6 1.5–1.6ROR 1.6 · calibrated p 0.717	1.6 EB05 1.5 · IC025 +0.6	Labeled adverse reaction exact term	age-adj. PRR 1.5 · serious PRR 1.5 · ♀ 76% (drug 53%)	NCT00384930: 1/209 (0.5%) on Tadalafil; 1/212 (0.5%) control
Pain	3,400	1.2 1.1–1.2ROR 1.2 · calibrated p 0.420	1.2 EB05 1.1 · IC025 +0.2	Labeled adverse reaction exact term	age-adj. PRR 1.2 · serious PRR 1.1	NCT00384930: 1/209 (0.5%) on Tadalafil (serious AE)
Pain in extremity	3,387	2.4 2.4–2.5ROR 2.5 · calibrated p 0.820	2.4 EB05 2.3 · IC025 +1.2 3/3 methods agree	Labeled adverse reaction exact term	age-adj. PRR 2.2 · serious PRR 2.2	NCT00384930: 3/209 (1.4%) on Tadalafil
Asthenia (weakness)	3,385	1.9 1.8–2.0ROR 1.9 · calibrated p 0.909	1.9 EB05 1.8 · IC025 +0.9	Labeled adverse reaction exact term	age-adj. PRR 1.8 · serious PRR 1.4	NCT00384930: 1/209 (0.5%) on Tadalafil; 1/212 (0.5%) control

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.

Fractional exhaled nitric oxide increased — n=123, PRR 530.1
Malignant melanoma stage ii — n=75, PRR 189.2
Malignant melanoma stage i — n=97, PRR 116.0
Infusion site pustule — n=42, PRR 104.7
Malignant melanoma stage iii — n=60, PRR 88.0
Catheter site vesicles — n=55, PRR 84.9
Catheter site pruritus — n=245, PRR 81.9
Malignant melanoma stage iv — n=79, PRR 80.9
Catheter site rash — n=117, PRR 73.8
Catheter site irritation — n=78, PRR 68.1

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 Tadalafil?

In FDA FAERS, the most frequently co-reported reaction terms for Tadalafil are dyspnoea, headache, diarrhoea, nausea, fatigue, dizziness. 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 Tadalafil have an FDA boxed warning?

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

Do FAERS signals prove that Tadalafil 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 0a9cf85a-c17d-6890-e063-6394a90a93e9, effective 20250304; matched on openfda.generic_name.exact:"TADALAFIL" AND openfda.product_type:"HUMAN PRESCRIPTION DRUG")
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, 1,239 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
ClinicalTrials.gov API v2 (query TADALAFIL, results-bearing studies sorted by enrollment)

Page generated 2026-10-14. 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.