Levetiracetam (KEPPRA)
Chemical
An acetamide 2nd gen anti-epileptic not chemically related to other anti-epileptics
Use
Tx epilepsy
Presentation
PO tablets (IR & ER)
Clear, colourless solution 100mg/mL
Dose
500mg BD → up to 3g/day
Route
PO/IV (dose is the same)
Onset
1hr → reaches SS after 2days of BD dosing
MoA (mechanism)
- Binds synaptic vessel protein SV2A
- Inhibits Ca2+ channel
- ↓NT release
- ∴impedes impulse conduction
PD
CNS – ↓seizures, impedes impulse conduction
PK
A
Excellent
100% OBA
Delayed by food
D
<10% PPB
VD 0.5L/kg
∴doesn’t compete with other drugs for binding
M
Enzymatic hydrolysis of acetamide group
No active metabolite
No CYP450 metabolism
E
66% excreted unchanged
Metabolite renally excreted
Needs dose adjustment in renal failure
Adverse Effects
Favourable because minimal drug interactions (cf. Phenytoin)