Zonisamide (AD 810), a sulfonamide anticonvulsant, is approved for use as an adjunctive treatment in adults with partial-onset seizures. It may inhibit a carbonic anhydrase although this is not one of the main mechanisms of action. Zonisamide may act by blocking repetitive firing of voltage-gated sodium channels results in a reduction of T-type calcium channel currents, or by binding allosterically to GABA receptors. This latter action may lower the uptake of the inhibitory neurotransmitter GABA while increasing the uptake of the excitatory neurotransmitter glutamate.

CA V (human):20.6 nM (Ki), CA II (human):35.2 nM (Ki)

Zonisamide可影响多巴胺活性,为缺血小鼠模型提供保护,并影响抗氧化系统.Zonisamide减缓DA代谢物DOPAC、DA和酪氨酸羟化酶在弱纹状体中含量的降低速度.Zonisamide（10和30 mg/kg）通过剂量依赖的方式产生止痛作用和抗痛觉过敏,这些作用分别通过机械刺激(von Frey测试法)和响应热刺激(足底痛觉测试)的撤回阈值提高得到证明.在未结扎小鼠体内,Zonisamide对严重的热刺激和机械伤害具有镇痛作用.在大鼠体内,Zonisamide使纹状体体积从载体处理对照组的78%降低为8%,皮质梗死体积从68%降低为6%.在大鼠体内, Zonisamide也会降低5个海马区(脑下脚,CA3,CA1,CA4,和齿状回)的神经元坏死.在患有海马癫痫的大鼠体内,Zonisamide使脑皮层和海马体中EAAC-1蛋白质数量增加,并下调GABA转运蛋白GAT-1. 在乌拉坦麻醉的大鼠体内,Zonisamide抑制50 mM KCl诱发的海马谷氨酸释放,AUC 为60 min,使之从9.2 mM降低为5.8 mM,也会抑制Ca2+对KCl诱发的海马谷氨酸释放的刺激作用.

Zonisamide对体外单胺氧化酶B活性具有抑制作用,IC50为25 μM。