Adjunct in partial seizures.
Swallow whole. ≥16yrs: initially 100mg once daily; may increase at intervals of at least 2 weeks by 100mg/day in 1 or 2 divided doses. Usual range: 100–400mg/day in 1 or 2 divided doses; usual max 600mg/day.
<16yrs: not recommended.
Discontinue or monitor closely if rash occurs. Renal failure: not recommended. Renal or hepatic impairment: titrate more slowly and monitor more frequently. Depression. Suicidal tendencies (monitor). Maintain adequate hydration. Exposure to extreme heat; monitor closely for oligohidrosis and hyperthermia (esp. children). Monitor baseline serum bicarbonate and periodically during treatment; consider reducing dose or discontinuing if metabolic acidosis occurs. Avoid abrupt cessation. Women of childbearing potential: use effective contraception. Elderly. Labor & delivery. Newborns. Pregnancy (Cat.C). Nursing mothers: not recommended.
Serum levels may be affected by CYP3A4 inducers or inhibitors. Caution with other drugs that interfere with temperature regulation (eg, anticholinergics, carbonic anhydrase inhibitors). Caution with concomitant alcohol or other CNS depressants.
CNS effects (eg, somnolence, anorexia, dizziness, headache, agitation, fatigue, ataxia, confusion, difficulty with memory and/or concentration, depression, insomnia, abnormal vision or speech), GI upset/pain, paresthesia; kidney stones, metabolic acidosis; rarely: Stevens-Johnson syndrome, toxic epidermal necrolysis, aplastic anemia, agranulocytosis, oligohidrosis, hyperthermia.