Effects of 2% ibopamine on pupil, refraction, anterior segment anatomy and intraocular pressure.

The aim of the study was to determine the effects of a dopaminergic drug, 2% ibopamine, on the pupil, intraocular pressure and other ocular and ultrasound biometric variables. Thirty healthy subjects and 15 patients with primary open-angle glaucoma, aged from 40 to 78 years (mean age: 59.2 +/- 11), were included in two prospective open controlled trials. In the first, the mydriatic effect of 2% ibopamine and its inhibition and reversibility were evaluated in 15 healthy subjects using the alpha(1)-adrenergic drug, 0.5% dapiprazole. In the second, refraction, visual acuity, pupil diameter, intraocular pressure and 5 A-scan ultrasound biometric variables were evaluated in 15 healthy subjects and in 15 glaucoma patients. As early as forty min after administration of 2% ibopamine, a marked mydriatic ef feet (7.3 vs 3.9 mm; P < 0.0001), which was completely inhibited or reversed by 0.5% dapiprazole, was detected. The drug induced no changes in refraction, visual acuity or Ascan ultrasound biometric variables in any of the subjects examined. In healthy subjects, the intraocular pressure values were not changed to a statistically significant extent (13.8 vs 14.8 mm HE; P = 0.668), whereas a slight, though significant, hypertensive effect (24 vs 22.2 mm Hg, P = 0.002) was observed in the glaucoma patients. The study confirms the intense mydriatic effect of 2% ibopamine with no changes in refraction, visual acuity or A-scan ultrasound biometric variables, The drug has no effect on intraocular pressure in healthy subjects, but induces a significant hypertensive effect in patients with initial glaucoma. This characteristic could be used for early diagnosis of primary open-angle glaucoma.