Visual disturbances associated with quinidine and quinine.

Obscurations of vision were experienced by three patients taking quinidine and by two patients taking quinine. In four, transient symptoms developed on exposure to light after first awaking in the morning, and in the fifth, there was persistent photophobia. In two patients, there was a large central scotoma, in one, swirling dark clouds, and in the fourth, flickering of vision. The duration was 1 to 4 minutes in three patients and 45 to 60 minutes in one patient. The symptoms, which are benign, may be confused with the prodromal visual manifestations of thrombotic cerebrovascular disease.