Therapeutic Strategy - Clinical Pharmacology of Antiseizure Drugs

THERAPEUTIC STRATEGY

In designing a therapeutic strategy, the use of a single drug is pre-ferred, especially in patients who are not severely affected and who can benefit from the advantage of fewer adverse effects using monotherapy. For patients with hard-to-control seizures, multiple drugs are usually utilized simultaneously.

For most of the older antiseizure drugs, relationships between blood levels and therapeutic effects have been characterized to a high degree. The same is true for the pharmacokinetics of these drugs. These relationships provide significant advantages in the development of therapeutic strategies for the treatment of epilepsy. The therapeutic index for most antiseizure drugs is low, and toxicity is not uncommon. Thus, effective treatment of seizures often requires an awareness of the therapeutic levels and pharmacokinetic properties as well as the characteristic toxicities of each agent. 

Measurements of antiseizure drug plasma levels can be very useful when combined with clinical observations and pharmacokinetic data (Table 24–2). The relationship between seizure control and plasma drug levels is variable and often less clear for the drugs marketed since 1990.