From the Guidelines
Status myoclonus treatment should prioritize the use of levetiracetam, valproate, or fosphenytoin as second-line agents after benzodiazepines, as they have similar efficacy in treating seizures refractory to benzodiazepines, according to the most recent guidelines 1.
Treatment Approach
Status myoclonus treatment typically involves a multi-faceted approach targeting the underlying cause while providing symptomatic relief.
- First-line medications include benzodiazepines, particularly clonazepam and diazepam.
- Valproic acid and levetiracetam are effective options, particularly in post-hypoxic myoclonus, with levetiracetam being used at 500-1500mg twice daily 1.
- For refractory cases, combination therapy may include adding other medications.
- In severe acute cases, propofol or midazolam infusions may be necessary in an ICU setting.
Medication Options
- Levetiracetam can be used at 500-1500mg twice daily, particularly in post-hypoxic myoclonus 1.
- Valproic acid is often effective at doses of 500-1500mg daily divided into 2-3 doses, with blood levels monitored to maintain 50-100 μg/mL.
- Clonazepam, sodium valproate, and levetiracetam are antimyoclonic drugs that may be effective in post-anoxic myoclonus 1.
Supportive Care
Supportive care, including management of secretions, prevention of aspiration, and physical therapy, is essential alongside pharmacological treatment. The effectiveness of these medications relates to their enhancement of GABAergic inhibition or modulation of neuronal hyperexcitability in the brain networks responsible for the abnormal muscle contractions, as noted in recent guidelines 1.
From the FDA Drug Label
- 2 Myoclonic Seizures in Patients with Juvenile Myoclonic Epilepsy Levetiracetam in Sodium Chloride Injection is indicated as adjunctive therapy in the treatment of myoclonic seizures in adults with juvenile myoclonic epilepsy. Myoclonic Seizures in Patients with Juvenile Myoclonic Epilepsy Treatment should be initiated with a dose of 1000 mg/day, given as twice-daily dosing (500 mg twice daily) Dosage should be increased by 1000 mg/day every 2 weeks to the recommended daily dose of 3000 mg.
Status myoclonus treatment with levetiracetam (IV) is indicated as adjunctive therapy in the treatment of myoclonic seizures in adults with juvenile myoclonic epilepsy.
- The recommended initial dose is 1000 mg/day, given as twice-daily dosing (500 mg twice daily).
- The dosage should be increased by 1000 mg/day every 2 weeks to the recommended daily dose of 3000 mg 2.
From the Research
Status Myoclonus Treatment
The treatment of status myoclonus is based on the underlying pathophysiology of the condition.
- Status myoclonus of cortical origin can be treated with medications such as levetiracetam, valproic acid, and clonazepam 3, 4, 5, 6, 7.
- For subcortical and brainstem myoclonus, clonazepam can be used as a first-line agent, while levetiracetam and valproic acid can also be tried 4, 6, 7.
- Spinal myoclonus does not respond to anti-epileptic drugs, and clonazepam is a first-line agent, with botulinum toxin treatment being useful for focal cases 4, 6.
- In cases where the etiology of the myoclonus cannot be reversed or treated, symptomatic treatment of the myoclonus itself may be warranted 6.
Treatment Approaches
Different treatment approaches can be used for status myoclonus, including:
- Medications such as levetiracetam, valproic acid, clonazepam, and piracetam 3, 4, 5, 6, 7.
- Botulinum toxin treatment for focal cases of spinal myoclonus 4, 5, 6.
- Deep brain stimulation targeting the globus pallidus pars-interna bilaterally for myoclonus-dystonia when pharmacological treatments have been exhausted 4.
- A ketogenic diet can be considered if other treatments fail 7.
Classification and Treatment
The classification of status myoclonus can help guide treatment, with different physiologies responding to different treatments: