Inclusion Criteria:  1. Female or male aged ≥ 18 years. 2. Acute ischemic stroke within 48 hours of onset 3. Examination to exclude intracranial hemorrhage 4. Provision of informed consent.  Exclusion Criteria:  1.Head CT or MRI suggests the presence of intracranial hemorrhagic disease 2.Patients with cerebral embolism or suspected cerebral embolism with severe atrioventricular block disease, atrial fibrillation, myocardial infarction, heart valve disease, infective endocarditis, heart rate less than 50 beats per minute 3.Abnormal liver function (transaminase ALT or AST exceeding the upper limit of normal), abnormal renal function (creatinine exceeding the upper limit of normal), or suffering from other serious systemic diseases, etc 4.Allergy to Butylphthalide