RT Journal Article
SR Electronic
T1 THE EFFECTS OF ANTACIDS ON THE ABSORPTION OF ORALLY ADMINISTERED PENTOBARBITAL IN THE RAT
JF Journal of Pharmacology and Experimental Therapeutics
JO J Pharmacol Exp Ther
FD American Society for Pharmacology and Experimental Therapeutics
SP 124
OP 131
VO 179
IS 1
A1 ARYEH HURWITZ
A1 MICHAEL B. SHEEHAN
YR 1971
UL http://jpet.aspetjournals.org/content/179/1/124.abstract
AB Studies were done in rats to evaluate possible interactions between antacids and pentobarbital administered by gastric intubation. Magnesium and aluminum hydroxides both retard gastrointestinal sodium pentobarbital absorption, lowering blood levels and preventing or delaying the onset of sleep. Magnesium hydroxide, by raising the gastric pH, shifts the pentobarbital to the ionized, unabsorbable form. Aluminum hydroxide acts by retarding gastric emptying, markedly increasing the fluid volume and pentobarbital retained in the stomach. This property, which greatly exceeds the gastric retention after atropine, is shared by dissociable aluminum salts and another trivalent cation, lanthanum, but not by magnesium or calcium. Although the rate of pentobarbital absorption is slowed, the total amount of 14C-pentobarbital absorbed, as measured by urinary excretion, is unaltered. An antacid containing both magnesium and aluminum hydroxides retards sodium pentobarbital absorption, lowering blood and brain levels of the hypnotic and delaying its pharmacologic effect. © 1971 by The Williams & Wilkins Company