Cialis (Tadalafil) Real-World Evidence: What Registries and Observational Data Show Beyond Clinical Trials

Q: Is there real-world evidence that tadalafil works?

The observational study here addresses safety, not effectiveness. It measured diagnosed cardiovascular and hypotensive outcomes during periods when men likely had tadalafil plus an antihypertensive [1]. It did not measure erectile function or BPH symptom scores.

Q: Does tadalafil with blood pressure medication cause dangerous blood pressure drops?

The label reports small additional blood pressure reductions when tadalafil is taken with amlodipine, angiotensin II receptor blockers, bendroflumethiazide, enalapril, or metoprolol [2]. In the US cohort, diagnosed hypotension was recorded more often during periods with both tadalafil and an antihypertensive than during antihypertensive-only periods (adjusted incidence rate ratio for antihypertensive-only versus combined 0.79, 95% CI 0.71 to 0.89); the study does not establish that tadalafil caused the difference [1].

By HealthRX.com Editorial Team

Published May 25, 2026Updated Oct 30, 2026Last reviewed May 25, 2026

2 linked public sourcesEditorial, sourcing, and corrections policy

At a glance

Drug / tadalafil (Cialis), a PDE5 inhibitor approved for ED, BPH, and ED with BPH [2]
Real-world study / US electronic health record cohort with 127,849 tadalafil plus antihypertensive possession periods [1]
Main result / diagnosed hypotension and ventricular arrhythmia recorded less often in antihypertensive-only periods than combined periods (IRR 0.79 for each) [1]
Eye signal / two case-crossover studies of PDE5 inhibitors as a class suggested about a 2-fold NAION association; causality was not established [2]

What the US real-world study measured

The study used an Optum electronic health record database and selected adult men prescribed tadalafil, an antihypertensive, or both from January 2012 to December 2017 [1]. It compared 127,849 tadalafil plus antihypertensive possession periods with 821,359 antihypertensive-only periods; 126,120 were matched by propensity score [1].

Outcomes came from diagnostic codes and natural-language processing, not measured blood pressure [1]. Adjusted matched incidence rate ratios comparing antihypertensive-only with combined periods were all below 1 [1]. Two confidence intervals excluded 1: ventricular arrhythmia (0.79, 95% CI 0.66 to 0.94) and diagnosed hypotension (0.79, 95% CI 0.71 to 0.89) [1]. Antihypertensive-only periods therefore had lower recorded rates of these diagnoses than periods with both drugs, and the study does not establish that tadalafil caused the difference [1]. Possession periods reflect when men likely had the medicines, not confirmed use.

What the eye data show

Two case-crossover studies of PDE5 inhibitors as a class suggested an association with non-arteritic anterior ischemic optic neuropathy (NAION), with estimates of 2.15 (95% CI 1.06 to 4.34) and 2.27 (95% CI 0.99 to 5.20) [2]. The Cialis label says neither these studies nor the postmarketing reports establish cause, and other risk factors such as a crowded optic disc may contribute [2]. The label directs patients to stop tadalafil and seek medical attention for sudden vision loss in one or both eyes [2].

What the label says about cardiovascular limits

The Cialis label says it should not be used when sexual activity is inadvisable because of a man's cardiovascular condition [2]. It also lists cardiovascular groups in which Cialis is not recommended because they were excluded from its trials: myocardial infarction within 90 days, unstable angina or angina during intercourse, NYHA class 2 or greater heart failure within 6 months, uncontrolled arrhythmia, hypotension (<90/50 mm Hg) or uncontrolled hypertension, and stroke within 6 months [2]. Organic nitrates are contraindicated [2].

Frequently asked questions

Is there real-world evidence that tadalafil works?

The observational study here addresses safety, not effectiveness. It measured diagnosed cardiovascular and hypotensive outcomes during periods when men likely had tadalafil plus an antihypertensive [1]. It did not measure erectile function or BPH symptom scores.

Does tadalafil with blood pressure medication cause dangerous blood pressure drops?

The label reports small additional blood pressure reductions when tadalafil is taken with amlodipine, angiotensin II receptor blockers, bendroflumethiazide, enalapril, or metoprolol [2]. In the US cohort, diagnosed hypotension was recorded more often during periods with both tadalafil and an antihypertensive than during antihypertensive-only periods (adjusted incidence rate ratio for antihypertensive-only versus combined 0.79, 95% CI 0.71 to 0.89); the study does not establish that tadalafil caused the difference [1].

Is vision loss a risk with tadalafil?

Two case-crossover studies of PDE5 inhibitors as a class suggested an association with NAION, with estimates of 2.15 (95% CI 1.06 to 4.34) and 2.27 (95% CI 0.99 to 5.20); the label states these do not establish cause [2]. The label directs patients to stop tadalafil and seek medical attention for sudden vision loss in one or both eyes [2].

References

Nunes AP, Seeger JD, Stewart A, Gupta A, McGraw T. Retrospective Observational Real-World Outcome Study to Evaluate Safety Among Patients With Erectile Dysfunction (ED) With Co-Possession of Tadalafil and Anti-Hypertensive Medications (anti-HTN). J Sex Med. 2022;19(1):74-82. Retrospective Observational Real-World Outcome Study to Evaluate Safety Among Patients With Erectile Dysfunction (ED) With Co-Possession of Tadalafil and Anti-Hypertensive Medications (anti-HTN)
U.S. National Library of Medicine, DailyMed. Cialis (tadalafil) tablets, Lilly prescribing information. Cialis (tadalafil) tablets, Lilly label

Evidence overview for cialis tadalafil: Cialis (Tadalafil) Real-World Evidence: What Registries and Observational Data Show Beyond Clinical Trials