Methazolamide, a derivative of sulfonamide, is an inhibitor of carbonic anhydrase (CA) that potently inhibits isoenzymes of CA, CA II and CA IV with values of 50% inhibition concentration IC50 of 8.1 nM and 80.3 nM respectively. Methazolamide has been widely used to treat glaucoma for its ability to reduce the rate of fluid formation in the inner eye through slowing the formation of bicarbonate ions and subsequently resulting in reduction in sodium and fluid transport. Recent studies have revealed that methazolamide, while other CA inhibitos are not, also acts as an insulin sensitizer to suppress hepatic glucose production in vivo.
Reference
[1].Konstantopoulos N, Molero JC, McGee SL, Spolding B, Connor T, de Vries M, Wanyonyi S, Fahey R, Morrison S, Swinton C, Jones S, Cooper A, Garcia-Guerra L, Foletta VC, Krippner G, Andrikopoulos S, Walder KR. Methazolamide is a new hepatic insulin sensitizer that lowers blood glucose in vivo. Diabetes. 2012;61(8):2146-2154
[2].Chang X, Yan X, Zhang Y. Treat ankylosing spondylitis with methazolamide. Int J Med Sci;8(5):413-419
[3].Gudmundsdóttir E, Stefánsson E, Bjarnadóttir G, Sigurjónsdóttir JF, Gudmundsdóttir G, Masson M, Loftsson T. Methazolamide 1% in cyclodextrin solution lowers IOP in human ocular hypertension. Invest Ophthalmol Vis Sci. 2000;41(11):3552-3554.