MULTIPLE-DOSE ACTIVATED-CHARCOAL COMPARED TO URINARY ALKALINIZATION FOR THE ENHANCEMENT OF PHENOBARBITAL ELIMINATION

Background: Urinary alkalinization and multiple-dose activated charcoa l are modalities advocated for the enhancement of phenobarbital elimin ation in poisoned patients. However, no studies exist comparing the ef ficacy of these two means of elimination enhancement We compared their effects on the pharmacokinetic disposition of intravenously administe red phenobarbital. Methods: Ten healthy volunteers participated in eac h of three randomly ordered study phases. During each phase, 5 mg of i ntravenous phenobarbital per kilogram of body weight was administered During phase I, no interventions were made in attempt to enhance pheno barbital elimination. In phase II, participants underwent 24 hours of urinary alkalinization. Throughout phase III, volunteers received sir doses of activated charcoal and two doses of sorbitol over 24 hours. R esults: The phenobarbital elimination half-life was 148 hours, 47 hour s and 19 hours during the control, alkalinization and charcoal phases, respectively. Statistically significant differences in the eliminatio n of phenobarbital were detected when each of the following phases wer e compared: I vs II, I vs III and II vs llI. Conclusions: Bath urinary alkalinization nod multiple doses of activated charcoal are effective for the enhancement of phenobarbital elimination but multiple-dose ch arcoal was superior to urinary alkalinization in our study population.