Daily treatment with sildenafil (Viagra) or tadalafil (Cialis) for 6 months appears to be safe for the eyes, according to an industry-supported study in Archives of Ophthalmology.
Nearly 250 men without ophthalmologic abnormalities — and with mild or no erectile dysfunction — were randomized to receive tadalafil (5 mg), sildenafil (50 mg), or placebo daily for 6 months. (Both drugs are phosphodiesterase type 5 inhibitors, which could inhibit a retinal enzyme.)
The treatment and placebo groups did not differ in the primary electroretinographic endpoint (dark-adapted, combined standard b-wave amplitude) or in visual function, intraocular pressure, or ocular anatomy.
The authors point out that their findings may not be generalizable to men with preexisting eye conditions or those with moderate or severe ED.