AIM: To investigate the guiding role of individualized medication adjustment based on CYP2C19 metabolic typing in the treatment of ischemic stroke with clopidogrel, and to provide reference for clinical individualized medication. METHODS: The total of 80 patients with ischemic stroke were divided into the individualized drug instruction group with gene detection (n=40) and the control group without gene detection (n=40) according to whether they received CYP2C19 gene detection. According to the metabolism of CYP2C19, the individualized medication instruction group was divided into slow metabolic type, intermediate metabolic type, fast metabolic type and ultra-fast metabolic type. Patients with fast and ultra-fast metabolites were given clopidogrel dose of 75 mg once a day. Patients with intermediate metabolic type were given double clopidogrel dose of 150 mg once a day. Patients with slow metabolism were given tigrillo dose of 90 mg twice a day or aspirin dose of 100 mg once a day. The control group received 75 mg clopidogrel once a day. All patients enrolled in the groups were followed up for 3 months by outpatients or telephone. The incidence of vascular events and mRS scale scores were compared between the two groups. RESULTS: The incidence of vascular events in the individualized drug instruction group was significantly lower than that in the control group, and the incidence of mRS score(0-1) was significantly higher than that in the control group, with statistically significant differences (P<0.05). CONCLUSION: The individualized medication for patients with ischemic stroke by CYP2C19 gene detection can significantly reduce the incidence of adverse vascular events and improve the prognosis and living ability of patients.