Mexiletine

Class Ib

IV DoseNo IV form
Oral doseChildren: 1.4-5.1 mg/kg/dose, given q 8 hours.
May increase to 8.0 mg/kg/dose in infants.
Adults: 450-1200 mg/day divided TID
Levels0.8-2.0 ug/ml
Poor correlation with therapeutic efficacy
KineticsElimination half-life 6.3-11.8 hours in adults
Increased to 15.4 hours in heart failure.
Peak levels 1-3 hours after oral dose
Cautions 
InteractionsPhenytoin, rifampin increase clearance
PreparationsMexitil capsules: 150, 200, 250 mg
FDA approval in childrenno