John Libbey Eurotext

Myoclonus and seizures in progressive myoclonus epilepsies: pharmacology and therapeutic trials Volume 18, supplément 2, September 2016


1 IRCCS, Institute of Neurological Sciences of Bologna, Unit of Neurology,
Bellaria Hospital, Bologna, Italy
2 Montreal Neurological Hospital & Institute, Neurology & Neurosurgery and Human Genetics,
McGill University, Montreal, Canada
3 Kuopio Epilepsy Center, Department of Neurology, Kuopio University Hospital,
4 Centre Saint-Paul - Hôpital Henri-Gastaut,
Marseille, France
* Correspondence : Roberto Michelucci IRCCS, Institute of Neurological Sciences of Bologna, Unit of Neurology, Bellaria Hospital, via Altura 3, 40139 Bologna, Italy

Generalized motor seizures, usually tonic-clonic, tonic-vibratory, myoclonic or clonic, and stimulus-sensitive/action myoclonus are typical features of progressive myoclonus epilepsies (PMEs). Despite the introduction of many anticonvulsants, the treatment of these symptoms, particularly myoclonus, remains challenging, due to the incomplete and often transitory effects of most drugs. Moreover, treatment is only symptomatic, since therapy targeting the underlying aetiology for these genetic conditions is in its infancy. Traditional antiepileptic drugs for the treatment of PMEs are valproate, clonazepam, and phenobarbital (or primidone). These drugs may improve the overall performance of PME patients by decreasing their generalized seizures and, to a lesser extent, their myoclonic jerks. Newer drugs which have been shown to be effective include piracetam, levetiracetam, topiramate, zonisamide, and possibly perampanel for Lafora disease. The potential of other drugs (such as L-triptophan and N-acetylcysteine) and procedures (such as vagal and deep brain stimulation) has also been discussed. The available data on the efficacy of drugs are mainly based on small series or anecdotal reports. Two prospective, randomized, double blind studies investigating the novel SV2A ligand, brivaracetam, in genetically confirmed Unverricht-Lundborg patients have been performed with disappointing results. When treating PMEs, particular care should be paid to avoid drugs known to aggravate myoclonus or myoclonic seizures, such as phenytoin, carbamazepine, oxcarbazepine, lamotrigine, vigabatrin, tiagabine, gabapentin, and pregabalin. The emergency treatment of motor status, which often complicates the course of PMEs, consists of intravenous administration of benzodiazepines, valproate, or levetiracetam.