A process for the preparation of crystals of zonisamide containing residual 1,2-dichloroethane
of not more than 5 ppm, by adding an aqueous C2-4 alcohol to crystals
of zonisamide containing residual 1,2-dichloroethane of more than 5 ppm, removing
the 1,2-dichloroethane by azeotropic distillation, followed by collecting the precipitated
crystals from the residual mixture.
