A one year-review of anti-epileptic drug monitoring in Trinidad

ABSTRACT

OBJECTIVE: To audit anti-epileptic drug monitoring in tertiary hospitals in Trinidad. METHODS: Epileptic patients, from hospital clinics, who were receiving maintenance therapy and were referred for plasma drug level monitoring, gave informed consent and were enrolled. Blood collection was at trough levels of drug and coded plasma samples were analysed by competitive immunoassay on the TDx Monitoring system. RESULTS: All 93 patients consented to participate. Phenytoin and carbamazepine were the two major drugs prescribed. The use of multiple drugs did not influence the occurrence of seizures in the patients; (31 percent) receiving polytherapy. Phenobarbital was the most frequent agent added to the drug regime in 24/9 patients (83 percent). Low plasma levels of drugs were detected in 58 percent and 36 percent of patients receiving polytherapy with phenytoin and carbamazepine respectively; but an association was not found between the range of drug levels and the frequency of seizures. Seventy-seven (83 percent) patients reported good compliance. Plasma drug levels were significantly below normal (p=0.004) in patients who reported poor compliance. CONCLUSIONS: Multiple drug therapy did not influence the prognosis of seizure control in this study. Suspected non-compliance, drug toxicity and failure to individualize dosing are considerations for plasma level drug monitoring in the protocol for management of epilepsy.(Au)