Response to Tomsak, R. PDE5 inhibitors and permanent visual loss ( Int J Impot Res 2005; 17 : 547–549)

I stand by the facts, speculations and conclusions stated in my Perspective article. For those who have not read it, I quote directly, with new emphasis added, from the last three sentences of the paper: 'The major predisposing factor is the anatomic structure of the optic nerve (disc at risk) followed by systemic risk factors for atherosclerosis and arteriosclerosis.' The use of PDE5i in persons with one or more of these risk factors may increase the chance of developing NAION. The use of PDE5i and the development of NAION remains a rare, but well documented, event that requires further study. For those interested in more depth, I am adding the following selected references, which were not allowed in the original Perspective article format.1, 2, 3, 4