The printable version is no longer supported and may have rendering errors. Please update your browser bookmarks and please use the default browser print function instead.
Administration
- Type: Anticonvulsant
- Dosage Forms: 250; 250/5mL
- Routes of Administration: oral tablet, oral syrup
- Common Trade Names: Zarontin
Adult Dosing
- Start: 250mg PO bid
- May increase 250mg/day q4-7 days
- Taper dose based on tx response to D/C
- Max: 1.5 g/day
Pediatric Dosing
- 3-6 yo
- 20 mg/kg/day PO divided bid
- Start: 250 mg PO QD
- Max: 1.5 g/day
- Taper dose based on tx response to D/C
- 6+ yo
- 20 mg/kg/day PO divided bid
- Start: 250 mg PO QD
- Max: 1.5 g/day
- Taper dose based on tx response to D/C
Special Populations
Renal Dosing
- Adult:
- CrCl <10: Decrease dose 25%
- HD: Give after dialysis
- PD: No adjustment
- Pediatric:
- CrCl <10: Decrease dose 25%
- HD: Give after dialysis
- PD: No adjustment
Hepatic Dosing
- Adult: Not defined
- Pediatric: Not defined
Contraindications
Adverse Reactions
Serious
Common
Pharmacology
- Half-life: 56-60 hr
- Metabolism: Liver extensively; CYP450: 3A4 substrate
- Excretion: Urine primarily (<20% unchanged), bile/feces
Mechanism of Action
- Depresses motor cortex
- Elevates CNS convulsive stimuli threshold
See Also
References