International Journal of Physical Medicine & Rehabilitation
Open Access

Myoclonic Seizures

Myoclonic seizures are brief shock-like jerks of a muscle or group of muscles. They occur in a variety of epilepsy syndromes that have different characteristics. During a myoclonic seizure, the person is usually awake and able to think clearly.

The mainstays of medical therapy for myoclonic epilepsy are valproic acid (sodium valproate), ethosuximide, or benzodiazepines (clonazepam or clobazam).

Types and Causes. Myoclonic seizures are caused by abnormal electrical activity in the brain, which triggers the myoclonic muscle movements. Often, they are exacerbated by tiredness, alcohol, fevers, infections, photic (light) stimulation, or stress.

A myoclonic seizure is a single or series of jerks (brief muscle contractions). Each jerk is typically milliseconds in duration. Myoclonic status epilepticus is characterized by ongoing (> 30 minutes) irregular jerking, often with partially retained awareness.