In a small size placebo-controlled study of patients with documented early age-related macular degeneration (n=9), sildenafil (single dose, 100 mg) demonstrated no significant changes in visual tests conducted (visual acuity, Amsler grid, colour discrimination simulated traffic light, Humphrey perimeter and photostress).
V majhni s placebom kontrolirani študiji pri bolnikih s potrjeno zgodnjo starostno degeneracijo makule (n = 9) sildenafil v enkratnem 100- mg odmerku ni imel pomembnega vpliva na preiskave vida (ostrina vida, Amslerjeva mrežica, ločevanje barv na simuliranem semaforju, Humphreyev perimeter in fotostres).