A widely used erectile dysfunction medication may be associated with a greater risk of glaucoma when taken long-term to relieve urinary symptoms caused by an enlarged prostate, according to a large comparative study published online in the British Journal of Ophthalmology.

The findings suggest that men who use tadalafil (Cialis) over extended periods for these symptoms may benefit from closer monitoring of their eye health. Researchers say this may be especially important for people who already have glaucoma risk factors, including a family history of the disease or elevated pressure within the eye (ocular hypertension).

Tadalafil and Eye Health

Tadalafil belongs to a group of medications known as phosphodiesterase type 5 inhibitors (PDE5i), the same drug class that includes sildenafil (Viagra). These medications are widely used for erectile dysfunction, while tadalafil is also prescribed for urinary problems associated with an enlarged prostate.

Previous research has connected PDE5i medications with several types of eye problems, including disorders involving the optic nerve and the macula, which is the area of the retina responsible for detailed central vision.