The plasma levels in humans of pentobarbital were determined after intravenous administration of a 50 mg dose. It was found that pentobarbital is distributed in at least two kinetically distinct body compartments: a central, or “serum” compartment and a peripheral, or “tissue,” compartment. By use of established mathematical techniques, values were assigned to the rate constants controlling the distribution and overall elimination of the drug from the body. The oral absorption of pentobarbital in fasted and nonfasted subjects was determined by mathematical analysis of the plasma level data following oral administration of a 50 mg dose. It was found that the presence of food significantly reduces the apparent absorption rate constant but not the amount absorbed. The absorption of a second dose, given 1.5 hr after the first dose, in nonfasted subjects was not affected, and a rapid increase in plasma levels occurred after this administration.
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B. B. Brodie, J. J. Burns, L. C. Mark, P. A. Lief, E. Bernstein, and E. M. Papper. The fate of pentobarbital in man and dogs and a method for its estimation in biological materials.J. Pharmacol. Exptl. Therap.,109, 26–34 (1953).
S. Riegelman, J. Loo, and M. Rowland. Concept of a volume of distribution and possible errors in evaluation of this parameter.J. Pharm. Sci.,57, 128–133 (1968).
R. G. Crounse. Human Pharmacology of Griseofulvin. The effect of fat intake on gastrointestinal absorption.J. Invest. Dermatol.,37, 529–533 (1961).
T. Giannina, B. G. Steinitz, and A. Meli. Pathway of absorption of orally administered ethynyl-estradiol-e-cyclopentyl ether in the rat as influenced by vehicle of administration.Proc. Soc. Exptl. Biol. Med.,121, 1175–1179 (1966).
G. Levy and W. Jusko. Factors affecting the absorption of riboflavin in man.J. Pharm. Sci.,55, 285–289 (1966).
K. E. Price, Z. Zolli, Jr., J. C. Atkinson, and H. G. Luther. Antibiotic inhibitors I. The effect of certain milk constituents.Antibiot. Chemotherap. (N.Y.),7, 672–689 (1957).
J. Scheiner and W. A. Altermeier. Experimental study of factors inhibiting absorption and effective therapeutic levels of declomycin.Surg. Gynecol. Obstet.,114, 9–14 (1962).
J. O. Klein and M. Finland. The new penicillins.New Engl. J. Med.,269, 1019–1025 (1963).
H. MacDonald, V. A. Place, H. Falk, and M. A. Parker. Effect of food on absorption of sulfonamides in man.Chemotherapia,12, 282–285 (1967).
K. Kakemi, T. Arita, R. Hori, and R. Konishi. Absorption and excretion of drugs XXXII. Absorption of barbituric acid derivatives from rat small intestine.Chem. Pharm. Bull.,15, 1883–1887 (1967).
K. Kakemi, T. Arita, R. Hori, and R. Konishi. Absorption and excretion of Drugs XXXI. On the relationship between partition coefficients and chemical structures of barbituric acid derivatives.Chem. Pharm. Bull.,15(2), 1705–1712 (1967).
J. Sjegren, L. Solvell, and I. Karlsson. Studies on the absorption rate of barbiturates in man.Acta Med. Scand.,178, 553–559 (1968).
A. Hume, M. Bush, J. Renick, and B. H. Douglas. Comparison of gastric absorption of thiopental and pentobarbital in rat, man and dog.Arch. Int. Pharmacodyn. Therap.,171, 122–127 (1968).
S. Kojima, R. B. Smith, and J. T. Doluisio. Drug absorption V. Influence of food on oral absorption of phenobarbital in rats.J. Pharm. Sci.,60, 1639–1641 (1971).
L. W. Dittert, W.O. Griffen, John C. LaPiana, F. J. Shainfeld, and J. T. Doluisio. Pharmacokinetic interpretation of penicillin levels in serum and urine after intravenous administration.Antimicrobial Agents and Chemotherapy—1969, pp. 42–48 (1970).
M. Berman and M. F. Weiss.Users Manual for SAAM. National Institute for Arthritis and Metabolic Diseases, Bethesda, Md. (1968).
J. C. K. Loo and S. Riegelman. New method for calculating the intrinsic absorption rate of drugs.J. Pharm. Sci.,57, 918–928 (1968).
J. T. Doluisio, J. C. LaPiana, G. R. Wilkinson, and L. W. Dittert. Pharmacokinetic interpretation of dicloxacillin levels in serum after extravascular administration.Antimicrobial Agents and Chemotherapy—1969, pp. 49–55 (1970).
Abstracted from a thesis submitted by R. B. Smith to the Graduate School, in partial fulfillment of the Master of Science degree requirements.
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Smith, R.B., Dittert, L.W., Griffen, W.O. et al. Pharmacokinetics of pentobarbital after intravenous and oral administration. Journal of Pharmacokinetics and Biopharmaceutics 1, 5–16 (1973). https://doi.org/10.1007/BF01060024
- absorption kinetics
- oral pentobarbital
- effect of food on oral absorption of pentobarbital in humans
- pentobarbital pharmacokinetics
- intravenous and oral administration
- effect of food on barbiturate absorption in humans