The effect of activated charcoal on phenytoin pharmacokinetics.
OBJECTIVE
To examine the effect of administration of oral activated charcoal with or without sorbitol on the elimination of phenytoin.


METHODS
Emergency department of a rural teaching institution.


METHODS
Eight normal volunteers.


METHODS
Subjects received 15 mg/kg phenytoin as an IV infusion. During the first phase of the study, oral activated charcoal was administered to a total dose of 140 g over a ten-hour period. During the second phase of the study, phenytoin alone was administered.


RESULTS
Administration of activated charcoal resulted in a significant decrease in the area under the curve 0-inf (p = .008) and in total body clearance (P = .008). No difference in the effect on phenytoin pharmacokinetic parameters was noted when the charcoal was administered with or without sorbitol, but fewer gastrointestinal adverse effects were noted without sorbitol treatment.


CONCLUSIONS
Oral activated charcoal was shown to affect phenytoin pharmacokinetic parameters. Further pharmacokinetic/pharmacodynamic studies are warranted to determine if activated charcoal results in a faster recovery from phenytoin toxicity.
Rowden
A M
AM
Department of Pharmacy Services, Mary Imogene Bassett Hospital, Cooperstown, New York 13326.
Spoor
J E
JE
Bertino
J S
JS
D000284:Administration, Oral; D002606:Charcoal / Q000494:pharmacology*; D004064:Digestive System / Q000187:drug effects; D004347:Drug Interactions; D006207:Half-Life; D006801:Humans; D007262:Infusions, Intravenous; D008657:Metabolic Clearance Rate / Q000187:drug effects; D010672:Phenytoin / Q000097:blood / Q000493:pharmacokinetics*; D013012:Sorbitol / Q000009:adverse effects / Q000494:pharmacology
D002606:Charcoal; D013012:Sorbitol; D010672:Phenytoin