In one study, Russian scientists conducted two randomized, double-blind, placebo-controlled trials of 6-months and 24-months duration, with eye drops consisting of a one percent aqueous solution of N-Acetyl-Carnosine (NAC) administered as two drops twice daily. (1) They treated a total of 49 elderly patients (average age 65) with cataracts ranging in severity from minimal to advanced (but not to the point of requiring surgery); the total number of eyes affected was 76. Using a variety of sophisticated optical techniques, they monitored the condition of the cataracts, visual acuity, and glare sensitivity.
The eyes treated with N-Acetyl-Carnosine were substantially improved in 6 months: the measured transmissivity of the lenses increased in 42 percent of the eyes, by 12-50 percent; in 90 percent of the eyes, visual acuity improved by 7-100 percent; and in 89 percent of the eyes, glare sensitivity improved by 27-100 percent. These improvements were sustained for the duration of the 24-month trial. In no eyes was any worsening of the condition seen. By contrast, the condition of the untreated eyes in the control group worsened. Visual acuity dropped in 89 percent of the controls by 17-80 percent after 24 months.
Another interesting study by the same team also evaluated patients between the ages of 48 and 60, who had various degrees of eyesight impairment, but who did not have the symptoms of cataract. After a course of treatment ranging from 2 to 6 months, the conclusion was that the eye drops alleviated eye-tiredness and continued to improve eyesight (i.e. there was more clear vision). The subjects reported that the treatment “brightened” and “relaxed” their eyes. This is an important indicator that the eye drops have a value both for preventive purposes, as well as medical applications.
(1). Babizhayev MA, Deyev AI, Yermakova VN, Semiletov YA, Davydova NG, Kurysheva NI, Zhokotskii AV, Goldman IM. N-Acetylcarnosine, a natural histidine-containing dipeptide, as a potent ophthalmic drug in treatment of human cataracts. Peptides, 2001