We prospectively applied a protocol used to sedate children who required a liver biopsy. Sixty liver biopsies were performed on thirty pediatric patients to assess the effects of treatment. Sixteen patients had Type 1 Gaucher's disease of which seven had a platelet count between 50-100,000/mm3. All seven had bleeding time performed and when indicated, intravenous DDAVP (1-deamino-8-D-arginine vasopressin) was used to improve hemostasis. Fourteen patients had Niemann-Pick disease type C of which eight were significantly demented and uncooperative. Before liver biopsy, all patients were sedated with the following regimen: oral chlorpromazine (1 mg/kg) followed one hour later by intravenous meperidine (1 mg/kg) and pentobarbital (maximum dosage 6 mg/kg) administered by slow intravenous injection. Liver biopsies were obtained safely on all patients. Only 1 patient (2%) developed a potentially serious complication: an obstructed airway which was readily corrected by simple repositioning. Transient less serious complications occurred in another 7 patients (12%). There was no long term sequalae of the biopsy procedures. Our study indicates that with appropriate patient selection, this sedation protocol may be useful in pediatric patients requiring a liver biopsy.