Olanzapine + fosaprepitant

Olanzapine + fosaprepitant is a combination of two pharmaceutical agents used primarily for the prevention of chemotherapy-induced nausea and vomiting (CINV). Olanzapine is an atypical antipsychotic that acts as an antagonist at multiple neuronal receptors, including dopamine D1-D4, serotonin 5HT2A/2C/3/6, alpha-1 adrenergic, histamine H1, and muscarinic receptors. Its antiemetic effect is mainly attributed to antagonism at dopamine and serotonin receptors in the central nervous system[6]. Fosaprepitant is a prodrug of aprepitant and functions as a neurokinin-1 (NK1) receptor antagonist; it blocks substance P from binding to NK1 receptors in the brainstem emetic center, thereby reducing both acute and delayed phases of chemotherapy-induced emesis[3][5]. This combination has been studied for its efficacy in preventing CINV in patients receiving highly or moderately emetogenic chemotherapy regimens[4][8].