Of 71 patients with only bilateral macular drusen, 8 eyes in 7 patients (9.9%) developed exudative maculopathy over an average follow-up of 4.3 years (14.5% cumulative risk). Severe visual loss due to exudative maculopathy occurred in 7 eyes of 6 patients (8.5%) for a 5-year cumulative risk of 12.7%. Features of the drusen were analyzed, but only the association with focal hyperpigmentation (P less than 0.001) and more than minimal drusen confluence (P less than 0.05) were statistically significant. Older patients had more severe drusen. Photostress test delay did not correlate with visual acuity, age, or severity of drusen.