Zonisamide is an anticonvulsant and sulfonamide derivative that reduces neuronal hyperexcitability by blocking voltage-dependent sodium and calcium channels, thereby stabilizing neuronal membranes. When used for cluster headache, it helps modulate pain transmission and reduce the frequency and severity of attacks by potentially suppressing abnormal neuronal firing in the trigeminovascular system. Its mechanism of action suggests potential efficacy in preventing and managing the intense, recurring pain characteristic of cluster headaches.