Stopping Antiepileptic Drugs: When and Why?

Abstract

Opinion statementAfter a patient has initiated an antiepileptic drug (AED) and achieved a sustained period of seizure freedom, the bias towards continuing therapy indefinitely can be substantial. Studies show that the rate of seizure recurrence after AED withdrawal is about two to three times the rate in patients who continue AEDs, but there are many benefits to AED withdrawal that should be evaluated on an individualized basis. AED discontinuation may be considered in patients whose seizures have been completely controlled for a prolonged period, typically 1 to 2 years for children and 2 to 5 years for adults. For children, symptomatic epilepsy, adolescent onset, and a longer time to achieve seizure control are associated with a worse prognosis. In adults, factors such as a longer duration of epilepsy, an abnormal neurologic examination, an abnormal EEG, and certain epilepsy syndromes are known to increase the risk of recurrence. Even in patients with a favorable prognosis, however, the risk of relapse can be as high as 20% to 25%. Before withdrawing AEDs, patients should be counseled about their individual risk for relapse and the potential implications of a recurrent seizure, particularly for safety and driving.

Sensitivity of the UK Clinical Practice Research Datalink to Detect Neurodevelopmental Effects of Medicine Exposure in Utero: Comparative Analysis of an Antiepileptic Drug-Exposed Cohort

“…It is also possible that exposure misclassification may have played a role in the differences. In the CPRD, the prescription records did not appear to allow for a tapering of dose and in epilepsy AEDs are not routinely discontinued abruptly and tapering can take a number of months [18]. Manual review of the electronic prescription records for the nine NDD cases of WWE and reportedly no AED exposure demonstrated that two women had been estimated to have discontinued valproate just prior to pregnancy; however, if tapering of the dose did occur rather than an abrupt stop (as predicted by the algorithm), their window of exposure could have been extended to overlap with early gestation.…”

Early withdrawal of non-anesthetic antiepileptic drugs after successful termination of nonconvulsive seizures and nonconvulsive status epilepticus

“…In these instances, the bias is toward an increased risk of seizure recurrence following AED discontinuation [28]. Both randomized controlled trials and prospective studies have demonstrated that adult patients with known epilepsy who continue AED treatment have relapse rates of 22-28%, compared with 41-50% in withdrawal groups [29,30] although lower seizure relapse rates of 15% have been reported in AED withdrawal groups [31].…”

Seizure freedom is not adversely affected by early discontinuation of concomitant anti‐epileptic drugs in the EULEV cohort of levetiracetam users

“…Previous studies of AED discontinuation have often concerned withdrawal of AED treatment, particularly for patients in remission . The present study, however, investigates the question of discontinuation after introduction of an AED, and adds to the evidence that polypharmacy may be unnecessary .…”