Indications for ONFI:
Adjunctive treatment of seizures associated with Lennox-Gastaut syndrome (LGS).
Adults and Children:
<2yrs: not established. Tabs may be swallowed whole, scored, or crushed and mixed in applesauce. ≥2yrs: Give in divided doses twice daily (except for 5mg dose). ≤30kg: initially 5mg, then increase to 10mg on Day 7, then increase to 20mg on Day 14. >30kg: initially 10mg, then increase to 20mg on Day 7, then increase to 40mg on Day 14. Elderly, CYP2C19 poor metabolizers, mild to moderate hepatic impairment (Child-Pugh score 5–9): initially 5mg/day; titrate according to weight (as shown above) but to half the dose, an additional titration to max dose (20mg/day or 40mg/day, depending on weight) may be started at Day 21.
Risks from concomitant use with opioids.
Increased risk of drug-related mortality from concomitant use with opioids. Monitor for the emergence or worsening of depression, suicidal thoughts/behavior, and/or unusual changes in mood or behavior. Monitor for signs/symptoms of serious skin reactions (eg, SJS, TEN), esp. during the first 8 weeks of initiation or when re-introducing therapy; discontinue at the first sign of rash unless it's not drug-related. Avoid abrupt cessation; taper by decreasing total daily dose by 5–10mg/day on a weekly basis. Drug abusers. Severe renal or hepatic impairment or ESRD. Elderly. Neonates/infants. Pregnancy. Labor & delivery, nursing mothers: monitor.
Increased risk of profound sedation, respiratory depression, coma, and death with opioids; reserve concomitant use in those for whom alternative options are inadequate; limit dosages/durations to minimum required; monitor. May increase risk of sedation/somnolence with concomitant other CNS depressants, alcohol. May be potentiated by CYP2C19 inhibitors (eg, fluconazole, fluvoxamine, ticlopidine, omeprazole). May diminish effect of hormonal contraceptives (use non-hormonal forms). May need to adjust dose of drugs metabolized by CYP2D6.
Somnolence, sedation, drooling, constipation, pyrexia, lethargy, cough, UTI, aggression, insomnia, dysarthria, fatigue; hypersensitivity reactions.
Generic Drug Availability:
Tabs—100; Susp—120mL (w. 2 dosing syringes)