A large-scale study has found a potential association between long-term use of the erectile dysfunction drug tadalafil and an increased risk of glaucoma, a serious eye condition that can lead to irreversible vision loss.
Key findings from the research:
- Men aged 40 and older who took tadalafil were 22% more likely to develop glaucoma compared to those who did not use phosphodiesterase type 5 (PDE5) inhibitors, the drug class that includes tadalafil, commonly sold as Cialis.
- The study also found a 32% higher likelihood of developing high intraocular pressure and a 33% higher likelihood of developing primary open-angle glaucoma, the most common form of the disease.
The research, published in the British Journal of Ophthalmology, analyzed health records from nearly 74,000 men with lower urinary tract symptoms over a period of up to five years. The study compared 37,000 men prescribed tadalafil with a similar group that did not use PDE5 inhibitors.
What is glaucoma and why does it matter?
Glaucoma is a group of eye diseases that damage the optic nerve, often due to elevated pressure within the eye. It is a leading cause of irreversible blindness worldwide. Early stages of glaucoma typically do not present with noticeable symptoms, making regular eye exams critical for detection and management.
According to Dr. Valerie Kattouf, an optometrist at the Illinois Eye Institute who was not involved in the study, glaucoma can progress silently before symptoms such as peripheral vision loss become apparent. “Clinical findings of glaucoma are best detected in a comprehensive vision evaluation,” Kattouf noted.
Who is most at risk?
While the study highlights a statistical association, it does not establish a causal relationship. However, certain individuals may face higher inherent risks for glaucoma, including those with:
- A family history of the disease
- High intraocular pressure
- Severe nearsightedness
The study focused on men taking tadalafil for erectile dysfunction or enlarged prostate symptoms, many of whom may have been using the medication long-term. Daily use over extended periods was identified as a potential factor in the observed risk increase.
What should patients do?
Experts emphasize that individuals currently taking tadalafil should not discontinue use without consulting a healthcare provider. The potential benefits of the medication for treating erectile dysfunction or benign prostatic hyperplasia (BPH) must be weighed against the possible risks.
Routine eye exams, including tonometry (measurement of eye pressure) and optic nerve assessment, are recommended for early detection. Patients with risk factors or concerns are advised to discuss their medication regimen with an eye care professional.
The study does not call for regulatory action or changes in prescribing practices but underscores the importance of ongoing monitoring for patients using tadalafil long-term.