ABSTRACT
Pharmacologic principles applicable in the management of epileptic patients include those expressed in pharmacokinetics and pharmacodynamics. Experience from monitoring the blood levels of antiepileptic drugs over the past decades has shown that there is reasonable correlation between the administered dose and the plasma level. An individual patient typically shows higher levels with higher doses, but the same dose in mg/kg may produce quite different concentrations in different individuals. The actual effective and toxic levels for an individual patient may fall in or out of these ranges and are therefore determined empirically. The correlation between blood level and clinical effects, particularly intoxication, may change over time as tolerance develops. Markedly reduced binding is often seen in patients with uremia, chronic liver disease, or systemic lupus erythematosus. In patients with poor renal function, the uremic products compete for the biding sites, and structural change of binding proteins probably occurs from carbamylation.
