The purpose of this study was to examine using the original halometer glare test of the type of visual impairment mediated by the increased glare sensitivity (halos) and associated with poorer visual function in both the better and worse eyes of older adult drivers and older drivers with cataract. The clinically validated (by Innovative Vision Products Inc.) formula of 1% N-acetylcarnosine (NAC) lubricant eye drops were applied topically to the eyes of older drivers to reduce glare disability and improve distance acuities for driving. This was a randomized, double-blind, placebo-controlled study. The examined subjects consisted of 65 older adults with cataract in one or both eyes, and 72 adult drivers who did not have cataract in either eye. In the control group, comparison with baseline values showed some variability of data in gradual worsening of glare sensitivity at red and green targets and minimal VA changes over 4 months. In the NAC-treated group, 4-month follow-up generally showed an improvement in VA and a significant improvement in glare sensitivity at red and green targets was documented in worse and better eyes using a critical cut point halometer score for driving. The NAC-treated eyes had statistically significant difference in VA, glare sensitivity compared with the control group ( p < 0.001) at 4-month timepoint of treatment, as supported by the overall t-test results of the ratio of the follow-up data to the baseline values. Tolerability of NAC eyedrops was good in almost all patients, with no reports of ocular or systemic adverse effects. It would be advisable for traffic safety if a Halometer glare sensitivity test was implemented for vehicles and/or was regularly added to the requirements for a driver's licence. The results of this study provide a substantial basis for further evaluation of NAC in the treatment and prevention of vision impairment in the older population of drivers for legal driving. The developed ophthalmic drug NAC formula showed potential for the non-surgical treatment of age-related cataracts.