Epilepsy is a common and serious neurological disorder characterised by recurrent spontaneous seizures. Frontline pharmacotherapy includes small-molecule antiseizure drugs that typically target ion channels and neurotransmitter systems, but these fail in 30% of patients and do not prevent either the development or progression of epilepsy. An emerging therapeutic target is microRNA (miRNA), small noncoding RNAs that negatively regulate sets of proteins. Their multitargeting action offers unique advantages for certain forms of epilepsy with complex underlying pathophysiology, such as temporal lobe epilepsy (TLE). miRNA can be inhibited by designed antisense oligonucleotides (ASOs; e.g., antimiRs). Here, we outline the prospects for miRNA-based therapies. We review design considerations for nucleic acid-based approaches and the challenges and next steps in developing therapeutic miRNA-targeting molecules for epilepsy.Current versus future drugs for epilepsy: the need for change Epilepsy (see Glossary) is a common, often life-long brain disease characterised by recurrent, spontaneous seizures that are the result of hypersynchronous discharges of neurons [1]. There are more than 20 different small-molecule drugs in clinical use that reduce or prevent seizures in people with epilepsy. This is a remarkable achievement, certainly relative to the lack of treatments for many neurological disorders, and is owed to a solid mechanistic understanding of how seizures arise through imbalances between excitation and inhibition and the availability of good disease models that identify molecules with antiexcitability properties [2]. However, antiseizure drugs likely do not substantially alter the underlying pathophysiology of epilepsy, and one-third of patients are refractory to current treatments. Addressing this treatment gap is a major priority [1,3], and, increasingly, researchers are looking at substantially different targets.Acquired forms of epilepsy, such as TLE, have a limited genetic basis and probably arise from an earlier brain insult that leads to select cell loss, gliosis, neuroinflammation, and vascular and microscopic as well as macroscopic reorganisation of brain networks [4,5]. Because of this, single targets, such as ion channels, may be unsuitable or insufficient to overcome drug resistance, achieve disease modification, or prevent epileptogenesis [6] (Box 1). Novel approaches that can modify multiple targets may be necessary. Additionally, suitable target(s) may not reside on the outside of neurons but instead be intracellular. Both challenges could be solved by using RNAbased medicines such as ASOs, which offer virtually unlimited potential to target any gene, and small noncoding RNAs called microRNAs (miRNAs), which are 'multi-pathway' regulatory molecules (for a recent review on the general topic of RNA medicines, the reader is referred elsewhere [7]).The first miRNA medicine reached human trials in 2013 [8], and several others are in clinical testing. The versatility of ASO-based medicines was elegantly dem...