Levetiracetam
Mechanism :
The precise mechanism(s) by which levetiracetam exerts its antiepileptic effect is unknown. The antiepileptic activity of levetiracetam was assessed in a number of animal models of epileptic seizures. Levetiracetam did not inhibit single seizures induced by maximal stimulation with electrical current or different chemoconvulsants and showed only minimal activity in submaximal stimulation and in threshold tests. Protection was observed, however, against secondarily generalized activity from focal seizures induced by pilocarpine and kainic acid, two chemoconvulsants that induce seizures that mimic some features of human complex partial seizures with secondary generalization. Levetiracetam also displayed inhibitory properties in the kindling model in rats, another model of human complex partial seizures, both during kindling development and in the fully kindled state. The predictive value of these animal models for specific types of human epilepsy is uncertain. Levetiracetam is thought to stimulate synaptic vesicle protein 2A (SV2A), inhibiting neurotransmitter release.
Indication :
- Adjunct treatment for
- Primary generalized tonic clonic seizures
- Juvenile myoclonic epilepsy
- Partial seizures
- Neonatal Seizures
Contraindications :
Hypersensitivity to drug/class/component.
Avoid abrupt withdrawal.
Caution if pregnancy, renal impairment or psychiatric disorder.
Dosing :
<1 month:
Safety and efficacy not established.
1-6 months:
7 mg/kg PO 12 hourly. Increase by 7 mg/kg/dose PO 12 hourly till recommended dose of 21 mg/kg/dose 12 hourly.
6 months-16 years:
Start with 10 mg/day and go upto a maximum of 50 mg/kg/day upto 4 years of age and 60 mg/kg/day in children between 4-16 years in two divided doses. Max: 1500 mg every 12 hours.
>16 years:
500 mg PO 12 hourly, increase every 2 weeks to max dose of 1500 mg every 12 hours.
Adverse Effect :
Common Reactions: Pain, agitation, asthenia, headache, dizziness, irritability, infection, vomiting, hostility, depression, fatigue, nervousness, anorexia, somnolence, diarrhea, nausea, alopecia, neutropenia, anxiety, behaviour changes, ataxia, emotional lability, vertigo, leukopenia, amnesia, confusion.
Serious Reactions: Toxic epidermal necrolysis, aggressive, behaviour, Stevens-Johnson syndrome, psychosis, suicidality, neutropenia, withdrawal seizures if abrupt discontinuation.
Interaction :
Avoid/Use Alternative:
Ginkgo
Monitor/Modify Treatment:
Sevelamer
Renal Dose :
Dose in Renal Impairment GFR (mL/min)
| 50-79 | 500–1000 mg twice daily |
| 30-49 | 250–750 mg twice daily |
| <30 | 250–500 mg twice daily |
Dose in Patients undergoing Renal Replacement Therapies
| CAPD | Likely dialysability. 750 mg loading dose then 500–1000 mg daily |
| HD | Dialysed. 750 mg loading dose then 500–1000 mg once daily |
| HDF/High flux | Dialysed. 750 mg loading dose then 500–1000 mg once daily |
| CAV/VVHD | Likely dialysability. Dose as in GFR=30–49 mL/min |
Hepatic Dose :
Mild and moderate hepatic impairment: No dose reduction is required. Use with caution.
Severe hepatic impairment: Reduce dose by 50%.