• I. E. Leppik
Part of the Handbook of Experimental Pharmacology book series (HEP, volume 138)


Zonisamide is a synthetic 1,2-benzisoxazole derivative (1,2-benzisoxazole-3-methanesulphonamide). The anticonvulsant properties of zonisamide were not predicted from its chemistry; rather they were discovered by routine screening of various 1,2-benzisoxazole derivatives. Its formula is C8H8N2O3S, and its molecular weight is 212. It has a pK a of 9.66, so that its water solubility is dependent on the pH. Below a pH of 8, it has a solubility of only 0.8mg/ml, but it has a marked increase in solubility as the pH increases into the alkaline range. Although zonisamide is quite soluble in acetone it is much less soluble in methanol, ethanol, ether and chloroform. Its synthesis was first accomplished in 1972 by Uno et al. (1976).


Antiepileptic Drug Complex Partial Seizure Median Daily Dose Refractory Partial Seizure Progressive Myoclonic Epilepsy 
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© Springer-Verlag Berlin Heidelberg 1999

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  • I. E. Leppik

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