Treatment of phenobarbitone poisoning with repeated oral administration of activated charcoal

Six patients with moderate to severe phenobarbitone intoxication were treated with repeated oral doses (50 g) of activated charcoal following an initial dose of 50 to 100 g. All recovered more rapidly than would otherwise be expected with supportive care alone. The mean maximum rate of fall in plasma phenobarbitone concentrations corresponded to a half-life of only 6.2 +/- 2.5 h (normally three to five days); 62 to 93 per cent of the absorbed dose was eliminated within 24 h and the mean total body clearance of the drug during and for up to 12 h after administration of charcoal was 84 +/- 34 ml/min. Treatment with repeated oral doses of activated charcoal is simple and safe. It seems to be as effective as forced alkaline diuresis, haemodialysis and haemoperfusion for the removal of phenobarbitone following overdosage.