The use of flunarizine in the management of low‐tension glaucoma: A Color Doppler study

Abstract

The authors assess the efficacy of flunarizine in improving blood flow and perimetric indices in low-tension glaucoma (LTG). A group of 20 patients with LTG well-compensated by medical treatment underwent Color Doppler Imaging (CDI) of the ophthalmic artery and posterior ciliary arteries with peak systolic velocity (PSV) and Purcelot's index (PI) evaluation. Computerized perimetry was also performed to assess MD, SF and CPSD.The parameters were measured before and after three months' therapy with flunarizine.Data before and after flunarizine treatment were:Ophthalmic artery - The perimetric indices were modified as 6.426 (p<0.006); SF 5.05rt5.717 vs 2.937i 1. 780 (p<0.193); CPSD 10.198i13.392 vs 3.445k2.709 (p<0.093).Oral administration of flunarizine, a calcium channel-blocker which acts at a vascular and neuronal level, improves cm/sec (p<0.005); fOllOWS: MD -11.002i6.574 vs -6.604 f the blood flow indices for the optic nerve, improving thereby the perimetric indices in LTG.

Effect of Flunarizine, a Calcium Channel Blocker, on Intraocular Pressure and Aqueous Humor Dynamics in Monkeys

“…18 Calcium antagonists have also been reported to be neuroprotective in ischemia-reperfusion models in vivo 34,35 and in excitotoxicity models in which retinal ganglion cells and cortical neurons in cell culture were exposed to N-methyl-D-aspartate and glutamate 3,35 or in which nerve growth factor was withdrawn. 20 In addition, the effect of this class of agents on vascular smooth muscle could contribute to the improvement in optic nerve head or retinal blood flow measured in normal subjects and in patients with glaucoma after treatment with calcium channel blockers, 9,15,16,28 and to the improvement in visual field parameters observed in patients with normal tension glaucoma. [11][12][13]16 These experimental results indicate that calcium channel blockers may both reduce IOP and provide some degree of neuroprotection in glaucoma.…”

“…4 Flunarizine, a difluorinated piperazine derivative structurally related to cinnarizine, is classified as a type IV calcium antagonist and displays relative selectivity for L-type and T-type calcium channels. 22 It has been shown to reduce IOP in animal studies, [1][2][3][4] improve blood flow to the optic nerve head in patients with glaucoma 16 and attenuate the effects of ischemia and excitotoxicity to neuronal cells in experimental models. 3,17-21 The results of this study demonstrate a significant ocular hypotensive effect from single dosing of 0.5%, 1%, and 2% flunarizine applied topically to glaucomatous monkey eyes.…”

“…[6][7][8][9][10] Calcium antagonists have also been investigated as potential neuroprotective agents due to their role in modulating intracellular calcium levels and their effects on vascular smooth muscle. [9][10][11][12][13][14][15][16] A drug that combines an ocular hypotensive with a neuroprotective effect may be especially effective in the treatment of glaucoma, given the complexity of the underlying disease mechanisms. Flunarizine, a nonselective calcium channel blocker of L-type and T-type calcium channels, has been shown both to reduce IOP and to be neuroprotective in various experimental models.…”

“…Flunarizine, a nonselective calcium channel blocker of L-type and T-type calcium channels, has been shown both to reduce IOP and to be neuroprotective in various experimental models. [1][2][3][4][16][17][18][19][20][21] The purpose of this study is to evaluate the effect of flunarizine on IOP in glaucomatous monkey eyes and on aqueous humor dynamics in normal monkeys. …”

Magnesium: Effect on ocular health as a calcium channel antagonist

“…So that calcium channel blockers were evaluated for the management of glaucoma. In this sense, some calcium channel blockers have shown a positive effect on ocular blood flow and visual field in NTG [50,53,54]. But many systemic side effects such as hypotension, bradycardia, conduction disturbances and decrease in cardiac output can be seen during the calcium channel blocker intake, resulting in a restriction in the use for chronic diseases such as NTG [55].…”