Phase 3 RCT evaluating 0.75% phentolamine ophthalmic solution (POS) vs. placebo, administered once nightly for 14 days, in 145 subjects with dim light vision disturbances (DLD), mesopic pupil ≥5 mm, and reduced mesopic low-contrast visual acuity (mLCVA ≤30 ETDRS letters); included a post-hoc subgroup of post-keratorefractive surgery patients (n=25).
POS significantly improved mLCVA at Day 8 (13% vs. 3% placebo, p<0.05) and Day 15 (21% vs. 3% placebo, p<0.01), with significant reductions in self-reported glare, halos, and starburst severity at both time points (p<0.01); no significant difference in conjunctival hyperemia or vital signs between arms.
Short treatment duration (14 days) limits conclusions about long-term efficacy and safety; post-keratorefractive subgroup analysis was post-hoc and underpowered (n=25); the study does not report whether mLCVA improvements translated to functional real-world driving or nighttime performance outcomes.
For patients with symptomatic dim light disturbances and reduced mesopic contrast vision — including those post-LASIK or other keratorefractive surgery — nightly 0.75% phentolamine eye drops may offer meaningful short-term improvement in both visual acuity and photic symptoms. Adverse events were mild and transient, suggesting a favorable near-term tolerability profile, though longer-term data are still needed.
Explore related topics
