Fort Wayne, Ind. – A recent large‑scale study published in the British Journal of Ophthalmology has found an association between the erectile‑dysfunction medication Cialis (tadalafil) and a modest increase in glaucoma risk. Researchers examined anonymized medical records for 73,854 men aged 40 and older who were being treated for lower urinary‑tract symptoms linked to an enlarged prostate.
Study design and key findings
Half of the participants (36,927) had been prescribed tadalafil or another phosphodiesterase‑5 (PDE5) inhibitor, while the other half had not received any drug in this class. The two groups were matched on a wide range of factors that can affect eye health, including age, ethnicity, smoking status, cardiovascular disease, diabetes, high cholesterol, obesity, kidney disease, chronic obstructive pulmonary disease and other medications.
Over a follow‑up period of up to five years, the tadalafil group showed a hazard ratio of 1.22 for glaucoma, meaning a 22% higher relative risk compared with the matched non‑user group. The study also reported a 32% higher likelihood of ocular hypertension (elevated eye pressure) and a 33% higher chance of developing primary open‑angle glaucoma, the most common form of the disease. Users were similarly 33% more likely to begin treatment for glaucoma.
Interpretation and medical advice
Researchers emphasized that the findings do not prove tadalafil causes glaucoma; the study is observational and cannot establish causation. Nonetheless, they recommend that men who take Cialis, especially on a daily basis for prostate‑related urinary symptoms, consider a baseline comprehensive eye examination and regular monitoring if they have existing risk factors such as a family history of glaucoma, high myopia, or prior ocular hypertension.
Dr. Valerie Kattouf, an optometrist with the Illinois Eye Institute who was not involved in the research, noted that glaucoma often progresses without noticeable symptoms in its early stages. “A comprehensive eye exam is the best way to identify clinical signs of glaucoma,” she said, adding that patients with long‑term Cialis use may warrant closer observation.
Limitations of the research
The authors acknowledged several limitations. Because the analysis relied on existing medical records, they could not control for changes in medication use or health conditions that occurred after the study began. Patients were not randomly assigned to take tadalafil or a placebo, so unmeasured confounding factors could influence the results.
Importantly, a 22% increase in relative risk does not mean that 22% of Cialis users will develop glaucoma; it reflects the difference in likelihood between the matched groups.
Context within broader research
Previous investigations into PDE5 inhibitors and eye health have produced mixed results, with some studies suggesting possible effects on the optic nerve or macula, while evidence regarding glaucoma has remained limited. This new study adds to the body of knowledge but does not settle the question of causality.
For men who rely on tadalafil for erectile dysfunction or for managing urinary symptoms associated with an enlarged prostate, the practical takeaway is awareness rather than alarm. Regular eye exams can measure intra‑ocular pressure and assess the optic nerve, establishing a baseline for future comparisons.
What patients can do now
Physicians are encouraged to discuss eye health with patients considering long‑term tadalafil therapy, especially those who already have glaucoma risk factors. Patients should not discontinue their medication without consulting their healthcare provider, but they may wish to schedule an eye exam if one has not been performed recently.
The study’s authors call for further research to determine whether tadalafil itself contributes to glaucoma development and, if so, the underlying mechanisms.
Original reporting: WOWO News/Talk (Fort Wayne) — read the source article.
