A randomized crossover trial suggests that reducing eyedrop volume may improve intraocular pressure (IOP) control and medication utilization in patients with glaucoma or ocular hypertension.

The study, published in the Journal of Cataract & Refractive Surgery, evaluated a microvolume delivery adaptor from Nanodropper in patients using latanoprost 0.005% or timolol 0.5% monotherapy. Participants self-administered conventional drops or microdrops for 12 weeks before crossing over to the alternate method.

Microvolume delivery was associated with a greater reduction in IOP compared with standard drops (-1.6 mmHg vs -0.13 mmHg). The device also reduced premature bottle exhaustion: 83% of patients ran out of medication early with conventional bottles compared with 17% using the adaptor. Reported adverse effects were lower with microdrops (62% vs 83%).

The findings address a known limitation of topical therapy. Conventional drops typically exceed the ocular surface capacity of approximately 7 to 10 µL, leading to overflow, drug loss, and increased systemic exposure. By reducing drop size, microvolume delivery may increase the number of usable doses per bottle and limit interruptions in therapy. The authors concluded that microdrop delivery may support adherence and long-term disease control.