zonisamide + olanzapine

Zonisamide + olanzapine is a combination of two pharmaceutical drugs with distinct mechanisms and indications. Olanzapine is a second-generation (atypical) antipsychotic primarily used for the treatment of schizophrenia and bipolar I disorder. It acts as an antagonist at multiple neuronal receptors, including dopamine D2 receptor, serotonin 5HT2A receptor, serotonin 5HT2C receptor, serotonin 5HT3 receptor, serotonin 5HT6 receptor, alpha-1 adrenergic receptor, histamine H1 receptor, and several muscarinic receptors[3]. Zonisamide is an anticonvulsant approved as adjunctive therapy for partial-onset seizures in adults with epilepsy. Its mechanism involves blocking voltage-sensitive sodium channels and T-type calcium channels; it also modulates neurotransmitter synthesis and release[4][6]. Preclinical studies suggest that zonisamide may counteract olanzapine-induced weight gain by attenuating hyperphagia and metabolic changes associated with antipsychotic use[2].