Methazolamide-d₆is intended for use as an internal standard for the quantification of methazolamide by GC- or LC-MS. Methazolamide is a carbonic anhydrase inhibitor (IC₅₀= 130 nM).¹It reduces intraocular pressure and cerebrospinal fluid flow in a rat model of glaucoma. Methazolamide reduces electroshock-induced seizures in rats with an ED₅₀value of 19.2 mg/kg.²It also inhibits production of reactive oxygen species (ROS) in a primary cortical neuron (PCN) cellular model of subarachnoid hemorrhage (SAH) and reduces cerebral edema in a mouse model of SAH.³Methazolamide is larvicidal, with a 50% larvicidal concentration (LC₅₀) value of 724 ppm, but has no activity when administered in the diet to adultA. aegypti.⁴Formulations containing methazolamide have been used in the treatment of glaucoma.

1.Maren, T.H.Carbonic anhydrase: Chemistry, physiology, and inhibitionPhysiol. Rev.47(4)595-781(1967) 2.Gray, W.D., and Rauh, C.E.The anticonvulsant action of the carbonic anhydrase inhibitor methazolamide: Possible involvement of a noradrenergic mechanismEur. J. Pharmacol.28(1)42-54(1974) 3.Li, M., Wang, W., Mai, H., et al.Methazolamide improves neurological behavior by inhibition of neuron apoptosis in subarachnoid hemorrhage miceSci. Rep.635055(2016) 4.Francis, S.A., Taylor-Wells, J., Gross, A.D., et al.Toxicity and physiological actions of carbonic anhydrase inhibitors to Aedes aegypti and Drosophila melanogasterInsects8(1)2(2016)