Cyclobarbital as a test substance for oxidative drug metabolism in man. Findings in neuropsychiatric patients

  title={Cyclobarbital as a test substance for oxidative drug metabolism in man. Findings in neuropsychiatric patients},
  author={U. Breyer-Pfaff and H. Jerg and F. Petruch},
  journal={European Journal of Clinical Pharmacology},
SummaryThe disappearance of cyclobarbital from plasma has been followed in healthy volunteers and in neurological and psychiatric patients after oral administration of one tablet of Phanodorm®, containing cyclobarbital calcium 200 mg. Plasma levels were measured by a thin-layer chromatographic method with in situ densitometry. The average t1/2 in healthy female and male volunteers was 13.3 h, and with the assumption of complete availability a mean distribution coefficient of 0.69 l/kg−1 and a… Expand
1 Citations
Assessment of drug metabolism in hepatic disease: Comparison of plasma kinetics of oral cyclobarbital and the intravenous aminopyrine breath test
The cyclobarbital (CB) half-life was prolonged and the clearance reduced in patients with viral hepatitis, cirrhosis, or alcoholic liver damage as compared to data from 17 control subjects and discrimination between patients with and without disordered liver function was similar in the two drug elimination tests. Expand


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Amobarbital—a probe of hepatic drug oxidation in man
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Comparative drug elimination capacity in man‐glutethimide, amobarbital, antipyrine, and sulfinpyrazone
The apparent elimination half‐lifes were determined for 4 drugs that undergo hydroxylation in men and positive correlations were found among 3 out of 4 drugs, which would mean that one could, from the sulfinpyrazone half‐life in a given subject, predict the amobarbital half‐ life of the same individual within about ± 7 hours. Expand
Obesity and fasting—effects on drug metabolism and drug action in man
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The effect of ethanol on drug oxidations in vitro and the significance of ethanol-cytochrome P-450 interaction.
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Prediction of drug oxidation rates in man: Lack of correlation with serum gamma-glutamyl transpeptidase and urinary excretion of D-glucaric acid and 6β-hydroxycortisol
The results indicate that, in the absence of overt microsomal enzyme induction or inhibition, none of the tests would be of predictive value in the assessment of drug oxidation in clinical practice. Expand
Binding of amobarbital, pentobarbital and diphenylhydantoin to blood cells and plasma proteins in healthy volunteers and uraemic patients
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