BackgroundTo assess topical dorzolamide as medical therapy for idiopathic full‐thickness macular holes (FTMHs).MethodsRandomised, double‐blinded, placebo‐controlled, single‐centre clinical trial involving 32 patients with idiopathic small FTMHs (<400 ). Participants in both arms used topical dorzolamide 2% or saline thrice daily for 8 weeks with monthly OCT. Those with persisting FTMH underwent vitrectomy with ILM peel and gas tamponade. The primary outcome was the rate of FTMH closure at the end of treatment.ResultsBetween 6 March 2020 and 16 June 2023, 32 eligible patients were enrolled: 16 participants in each arm. All participants in both groups were included in the final analysis. At the final visit, 3 of 16 (18.8%) patients in both the topical dorzolamide and placebo group demonstrated closure. There was no statistically significant difference in the proportion of FTMH closure between the control and treatment group (p = 1.00), nor statistically significant difference in the mean change in best corrected visual acuity (BCVA; p = 0.909). There was no difference in the change in FTMH diameter between groups (p = 0.225). No serious adverse events were reported in either group.ConclusionTopical dorzolamide was safe but not superior to placebo in the functional and anatomical outcomes of FTMH.