Large ischemic stroke is a severe subtype of acute ischemic stroke (AIS), often leading to malignant cerebral edema, elevated intracranial pressure, and poor functional outcomes. Despite early aggressive treatment, malignant cerebral edema remains a major determinant of prognosis, even in cases of successful recanalization. Preclinical studies suggest that a pharmacological cocktail (PPA) may alleviate cerebral edema by modulating extracellular potassium balance, maintaining aquaporin-4 expression, and enhancing lymphatic drainage. This multicenter, randomized controlled trial (RCT) aims to assess the safety and efficacy of PPA in reducing cerebral edema and improving outcomes in patients with large ischemic stroke. The study will enroll 68 patients with MCA-territory infarction (80-300 mL infarct volume or ASPECTS 1-5), who are not undergoing decompressive craniectomy. Participants will be randomized to receive PPA therapy or standard treatment. The primary outcome is cerebral edema at 5-7 days, with secondary outcomes including 90-day functional outcomes (mRS) and safety assessments.