In the process of epilepsy drug treatment, drug dose adjustment and drug replacement are often encountered due to the poor effect of drugs and obvious drug adverse reactions, etc. The following are the principles that should be followed for antiepileptic drug dose adjustment and drug replacement. If the original antiepileptic drug is selected properly, it is best to measure the blood concentration and individualize the dose adjustment according to the blood concentration. If the original antiepileptic drug treatment is not effective or has large side effects, to change to another drug, the new drug must reach the maintenance dose, and the seizures stop, and then gradually withdraw the original drug. If the original combination of drugs is used, only one drug can be withdrawn at a time, and at least one month after the withdrawal of one drug, if there is still no seizure, then the second drug can be withdrawn. 4. If a seizure occurs during withdrawal, the withdrawal should be stopped and the drug dose should be restored to the pre-seizure level. 5. Common drug withdrawal methods: phenytoin sodium is reduced by 25 mg every 2 weeks in children and 50 mg every 2 weeks in adults; carbamazepine is reduced by 50 mg every 2 weeks in children and 100 mg every 2 weeks in adults; valproate is reduced by 100 mg every 2 weeks in children and 200 mg every 2 weeks in adults. In conclusion, the dose addition and reduction of antiepileptic drugs is based on the principle of blood concentration and clinical efficacy, while drug replacement is based on The principle of “add first, then reduce” is the principle.