Evaluation of different methods of enhanced elimination in phenobarbital overdose

ABSTRACT

Twenty-seven patients with phenobarbital overdose were treated by multipledoses of oral activated charcoal [n = 9], urinary alkalinization [n = 9] and acombined use of both modalities [n = 0]. Blood samples were taken from eachpatients at the time of admission [time 0], then at 6, 12, 24, 36 and 48 hourspost admission for the estimation of plasma phenobarbital concentrations. Half life, total body clearance and elimination rate constant of all patientswere calculated. It was found that multiple-dose activated charcoal [MDAC]and combined use of both MDAC and urinary alkalinization resulted in asignificant statistical reduction of phenobarbital half life and an increasein its total body clearance and elimination rate constant, when either of themwas compared with urinary alkalinization alone. MDAC alone was the mosteffective method for enhancing phenobarbital elimination in overdosedpatients, even more than the combined therapy, although there was nosignificant difference between them