Clonazepam add-on therapy for drug-resistant epilepsy.

Background: This is an updated version of the original Cochrane Review published in 2018, Issue 5. Epilepsy affects over 70 million people worldwide, and nearly a quarter of patients with seizures have drug-resistant epilepsy. People with drug-resistant epilepsy have increased risks of premature death, injuries, psychosocial dysfunction, and a reduced quality of life.

Objectives: To assess the efficacy and tolerability of clonazepam when used as an add-on therapy for adults and children with drug-resistant focal onset or generalised onset epileptic seizures, when compared with placebo or another antiepileptic agent.

Search Methods: For the latest update we searched the following databases on 4 June 2019: Cochrane Register of Studies (CRS Web), MEDLINE (Ovid) 1946 to 3 June, 2019. The Cochrane Register of Studies (CRS Web) includes the Cochrane Epilepsy Group Specialized Register, the Cochrane Central Register of Controlled Trials (CENTRAL), and randomised or quasi-randomised, controlled trials from Embase, ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform (ICTRP).

Selection Criteria: Double-blind randomised controlled studies of add-on clonazepam in people with resistant focal or generalised onset seizures, with a minimum treatment period of eight weeks. The studies could be of parallel or cross-over design.

Data Collection And Analysis: Two review authors independently selected studies for inclusion, extracted relevant data, and assessed trial quality. We contacted study authors for additional information.

Main Results: We found no double-blind randomised controlled trials which met the inclusion criteria.

Authors' Conclusions: There is no evidence from double-blind randomised controlled trials for or against the use of clonazepam as an add-on therapy for adults and children with drug-resistant focal or generalised onset epileptic seizures. Since the last version of this review no new studies have been found.