Adverse reactions were noted in 241 (4.82%) of 5,000 consecutive intravenous fluorescein angiographies of the retina. The most frequent adverse reactions were nausea (2.24%), vomiting (1.78%), and urticaria/pruritus (0.34%). No life-threatening reactions were noted. No significant difference in the rate of adverse reactions was found when angiography using 10% fluorescein was compared with angiography using 25% fluorescein.