What the Research Found About Tadalafil and Eye Health
The study, led by Yun Hsia and colleagues, used the TriNetX federated health research network to examine men aged 40 and older with a history of lower urinary tract symptoms (LUTS). Researchers compared men prescribed tadalafil with similar men who had LUTS but had not used phosphodiesterase type 5 inhibitors (PDE5 inhibitors).
The analysis covered patient records from 2012 through 2022. Men with a previous glaucoma diagnosis were excluded, and researchers used propensity-score matching to balance the groups on factors including age, race, existing medical conditions, kidney function, and other medications.
The final matched study population included 36,927 tadalafil users and 36,927 non-users. Participants were followed for up to five years, giving researchers a large group for examining the relationship between treatment and subsequent glaucoma diagnoses.
How Much Did Glaucoma Risk Increase?
The study found that tadalafil use was associated with a 22% higher relative risk of receiving a glaucoma diagnosis during follow-up. The adjusted hazard ratio was 1.22, with a 95% confidence interval of 1.12 to 1.33.
The five-year cumulative incidence was 3.93% among tadalafil users, compared with 3.16% among non-users. That represents an absolute difference of 0.77 percentage points, or fewer than one additional diagnosis per 100 people over five years in the observed groups.
These figures describe an association in the study population, not proof that tadalafil directly causes glaucoma. The distinction between relative and absolute risk is important: a 22% relative increase can correspond to a comparatively small difference in the proportion of people diagnosed.
Which Types of Glaucoma Were Associated With Tadalafil?
Researchers examined different glaucoma categories rather than treating all diagnoses as identical. The strongest reported associations were for primary open-angle glaucoma and ocular hypertension.
For primary open-angle glaucoma, the hazard ratio was 1.33, with a 95% confidence interval of 1.05 to 1.67. For ocular hypertension, the hazard ratio was 1.32, with a 95% confidence interval of 1.06 to 1.65.
Ocular hypertension means pressure inside the eye is higher than normal without necessarily indicating that glaucoma-related optic nerve damage has occurred. It is a risk factor that may warrant monitoring, depending on the person’s overall clinical assessment.
The study did not identify a statistically significant association with normal-tension glaucoma or primary angle-closure glaucoma. Tadalafil users were also more likely to begin glaucoma treatment during follow-up, with a hazard ratio of 1.33 and a 95% confidence interval of 1.20 to 1.47.
Why Might a Urinary Medication Be Linked to Glaucoma?
Tadalafil belongs to a group of medicines called PDE5 inhibitors. It works by inhibiting an enzyme involved in breaking down cyclic guanosine monophosphate, or cGMP, a signaling molecule that helps relax smooth muscle.
This action helps improve urinary symptoms associated with benign prostatic hyperplasia (BPH), a noncancerous enlargement of the prostate. Tadalafil was approved by the US Food and Drug Administration for erectile dysfunction in 2003 and for signs and symptoms of BPH in 2011.
The biological connection with eye pressure remains uncertain. Nitric oxide and cGMP signaling play a role in regulating the trabecular meshwork, a tissue involved in draining aqueous humor from the front of the eye through the Schlemm canal.
Changes in this pathway could theoretically influence fluid drainage, eye pressure, or ocular blood flow. However, the study did not directly measure intraocular pressure, and it did not establish the mechanism responsible for the observed association.
What Are the Limitations of the Study?
Although the matched cohort was large, the researchers relied on retrospective health records rather than a controlled clinical trial. Prescription and diagnostic codes cannot provide the same level of detail as direct clinical examinations and validated measurements.
The analysis also lacked information about the exact tadalafil doses patients took and whether they consistently followed their prescriptions. Researchers could not completely exclude other differences between users and non-users that might have influenced glaucoma diagnoses.
One possible factor is healthcare use. Patients receiving tadalafil may visit healthcare providers more often, creating additional opportunities for previously undetected glaucoma or elevated eye pressure to be identified.
The investigators conducted sensitivity analyses using one-, three-, and six-month lag periods to reduce the possibility that early diagnoses reflected disease that was already present but not yet recognized. The association remained consistent across these analyses, but that does not eliminate all potential sources of bias.
The findings also apply specifically to men taking tadalafil for lower urinary tract symptoms. They should not automatically be generalized to every person taking PDE5 inhibitors, including men who use these medications intermittently for erectile dysfunction.
What Should Men Taking Tadalafil Do?
The findings support awareness and appropriate eye care rather than alarm. Men taking tadalafil, particularly those with additional glaucoma risk factors, can discuss their eye health with their prescribing clinician and an eye-care professional.
Relevant risk factors include a family history of glaucoma, elevated baseline intraocular pressure, thin central corneas, and high myopia, or significant nearsightedness. Age is also important when assessing a person’s overall glaucoma risk.
A comprehensive eye examination may include tonometry to measure eye pressure, examination of the optic nerve, visual field testing, and assessment of the drainage angle when clinically indicated. No single test can rule out every form of glaucoma, and the appropriate evaluation depends on the patient’s circumstances.
Routine monitoring should follow an individual’s age, medical history, and eye-care professional’s recommendations. The study does not establish a new screening schedule that applies to every tadalafil user.
When Should You Seek Medical Attention?
Glaucoma can develop gradually without noticeable symptoms, particularly in its early stages. Regular eye examinations are therefore important for people at increased risk, even when their vision seems normal.
Seek urgent medical attention if you experience sudden severe eye pain, a red eye accompanied by blurred vision, halos around lights, or a sudden headache with nausea and vomiting. These symptoms can indicate acute angle-closure glaucoma or another eye emergency and should not be ignored.
Sudden vision loss or a new area of visual impairment also requires urgent assessment. Do not assume that a change in vision is a routine side effect of a prescribed medicine.
Frequently Asked Questions
Does tadalafil cause glaucoma?
The study found an association between tadalafil use for urinary symptoms and a higher rate of glaucoma diagnoses, but it cannot establish that tadalafil causes the condition. Further research is needed to determine whether the relationship is causal.
Should I stop taking tadalafil because of this research?
Do not stop or change a prescribed medication solely because of these findings without consulting your healthcare provider. Discuss your individual glaucoma risk, treatment benefits, and whether an eye examination is appropriate.
Can glaucoma be detected before symptoms appear?
Yes. Comprehensive eye examinations can identify signs of glaucoma before noticeable vision loss develops. Depending on the examination, an eye-care professional may assess intraocular pressure, optic nerve structure, visual fields, and the eye’s drainage angle.
What Happens Next in Glaucoma Research?
The findings were reported by Ophthalmology Times on August 25, 2026, and are based on research published online in the British Journal of Ophthalmology on August 4, 2026. The original study is titled Risk of glaucoma among patients using tadalafil for lower urinary tract symptoms: a multinational cohort study.
Further studies with detailed eye examinations, measured intraocular pressure, and better information about medication exposure may help clarify whether tadalafil directly affects glaucoma risk. Until stronger evidence is available, the practical next step for men taking the medication is to review their personal risk factors and keep up with recommended comprehensive eye examinations.
