In patients taking antiepileptic drugs for epilepsy, in order to effectively control epilepsy and reduce drug side effects, the drug concentration will be monitored regularly when applying antiepileptic drugs, and the drug dose will be adjusted at the right time. The adverse effects of AEDs on the central nervous system are apparent in the first few weeks of treatment and gradually subside later. Reducing the adverse effects of the initial phase of treatment can improve patient compliance, while enabling treatment to continue. Doses should be started at smaller doses and increased slowly until the seizure is controlled or the maximum tolerated dose is reached. Children should always be dosed according to their body weight, but the maximum dose should not exceed the adult dose. 2. If dose-related side effects (such as dizziness, drowsiness, fatigue, ataxia, etc.) occur during treatment, the patient can temporarily stop increasing the dose or reduce the current dosage as appropriate, and then continue to increase the dosage to the target dose after the side effects subside. 3. Reasonably arrange the number of doses to facilitate treatment and improve compliance, but also to ensure efficacy. If the seizures or adverse drug reactions show fluctuating forms (diurnal variation), consider changing the dosage form of AEDs (such as extended-release dosage form) or adjusting the duration and frequency of dosing to reduce the aggravation of side effects when the drug is at peak concentration and increase in seizures when it is at trough concentration. The following measures should be taken if AEDs fail: (1) Check patient compliance: Failure to take medication as prescribed is a common cause of antiepileptic treatment failure. Physicians should tell patients the importance of taking their medications on time and ask them to follow up regularly. Hospitals that are equipped to do so can monitor blood drug concentrations to understand patient compliance. (2) Reassess the diagnosis of epilepsy: determine whether the classification of seizures and syndromes is accurate based on the patient’s clinical presentation and EEG features. Examine the patient for the presence of an underlying progressive neurological disorder. (3) Select another effective one with fewer side effects and gradually increase the dose to seizure control or the maximum tolerable dose. Consider tapering the original AED after seizure control. The tapering should be done after the new drug reaches steady-state blood levels, and the tapering should be done slowly. (1) Single drug therapy is the basic principle of antiepileptic drug therapy. However, many patients with epilepsy are already taking one or more antiepileptic drugs at the time of consultation and their seizures are still not controlled. How to adjust the dose or change the medication: ① If the original AED is selected appropriately, adjust the dose. It is better to measure the blood concentration and individualize the dose adjustment. ②If the original AED is not properly selected, change to another new AED: when the patient’s new AED is changed to maintenance dose, if seizures stop, then slowly withdraw the original AED used. Seizure cessation means: for patients with frequent seizures there are five interictal periods without seizures (e.g., in the past, patients committed one seizure in 7-8 days on average and had 35-40 days without For patients with infrequent seizures, the AED can be gradually withdrawn after three months of no seizures. (3) Only one drug can be withdrawn at a time, and the second drug can be withdrawn after at least one month of withdrawal if there are still no seizures. (2) Withdrawal methods are as follows: ① Phenytoin sodium (Darentine 100 mg/tablet): 25 mg every two weeks for children; 50 mg every two weeks for adults. ② Carbamazepine (domestic 100 mg/tablet; Deltamethrin 200 mg/tablet): 50 mg every two weeks for children; 100 mg every two weeks for adults. ③ Valproate sodium (200 mg/tablet;): 100 mg every two weeks for children; (4) Depakene extended-release tablets (500 mg/tablet): 125 mg every two weeks for children; 250 mg every two weeks for adults. (3) If a seizure occurs during withdrawal, stop withdrawal and return the drug dose to the pre-seizure dose.