200 consecutive patients scheduled for intraocular cataract surgery under peribulbar block (PBB) were randomly divided into two groups of 100 patients each. All patients before cataract surgery randomly received peribulbar block either plain (pH 5.4) or pH-adjusted (pH 6.8 range 6.7–6.9) 0.75% bupivacaine labelled A and B respectively. This was done to make anesthetic unaware of the mixture to be administered for peribulbar block (Double Blind Technique). Hyaluronidase was added to both solutions prior to peribulbar block. Observation of ocular movements in all four quadrants at interval of 1 minute was assessed upto maximum 20 minutes and the time of onset of akinesia of the globe was noted. After 20 minutes interval of time no effect of PBB then the need for supplementary injections were also recorded by an independent observer (Supervisor). The relative efficacy of the different anesthetic solutions A or B was compared in patients who underwent intraocular cataract surgery. In both groups of patients, eyes receiving peribulbar block with the pH-adjusted solution showed a shorter onset of time to partial akinesia of the globe (P < 0.05). However, there was no difference between the solutions in the time to complete akinesia of the globe, but the number of supplementary injections required for an effective block with the pH-adjusted solution was increased. Onset time to akinesia of the lateral and superior rectus muscles was shortened in patients receiving the pH-adjusted solution but there were minimal effects on the medial and inferior recti muscle.