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Interactions between smectite, a mucus stabilizer, and acidic and basic drugs

In vitro and in vivo studies


The interaction of phenylbutazone and diazepam with smectite were studied in in-vivo and in-vitro. The kinetics of both drugs were investigated in healthy subjects after oral administration as monotherapy or in association with smectite. Smectite did not substantially alter the kinetics of phenylbutazone, whereas the peak plasma concentration of diazepam was reduced to 91%, and the time of peak concentration was prolonged by 153% of the control values. The in-vitro investigations were conducted at pH 5.5 and 8 and showed that there was no interaction between phenylbutazone and smectite, but that it adsorbed diazepam. The findings suggest that smectite delays the absorption of basic drugs and does not alter the absorption kinetics of acidic drugs.

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  1. Albengres E, Le Parco JC, Tillement JP (1979) Beidellite (or aluminium silicate) and digoxin, checking of a suspected drug interaction by in vivo and in vitro assays. In: Rietbrock N, Woodcock B, Neuhaus G (eds) Methods in clinical pharmacology, pp 323–328

  2. Barr WH, Adir J, Garreston L (1971) Decrease of tetracycline absorption in man by sodium bicarbonate. Clin Pharmacol Ther 12: 779–784

    Google Scholar 

  3. d'Athis P, Richard MO, de Lauture D, Rey E, Bouvier d'Yvoire M, Clement E, Olive G (1981) Etude comparative des biodisponibilités de 2 formes de spironolactone. Thérapie 36: 443–449

    Google Scholar 

  4. Hurwitz A, Sheehan MB (1971) The effect of antiacids on the absorption of orally administered pentobarbital in rat. J Pharmacol Exp Ther 179: 124–131

    Google Scholar 

  5. Lucarotti RL, Colaizzi JL, Barry H, Poust RI (1952) Enhanced pseudophedrine absorption by concurrent administration of aluminium hydroxide gel in humans. J Pharm Sci 61: 903–905

    Google Scholar 

  6. Paul HE, Harrington CM (1952) Adsorption characteristics of adriamycin and terramycin on aluminium hydroxide gel and on bismuth subsalicylate preparation. J Am Pharmacol Assoc 41: 50

    Google Scholar 

  7. Porubcan LS, Born SG, White JL, Hem SL (1979) Interaction of digoxin and montmorillonite: mechanism of adsorption and degradation. J Pharm Sci 68 (3): 358–361

    Google Scholar 

  8. Scagliola N, Julien R, Dreux C (1976) Microméthode de dosage du diazépam dans le sang par chromatographie gazliquide. Ann Biol Clin 34: 27–32

    Google Scholar 

  9. Wagner JG (1975) Fundamentals of clinical pharmacokinetics. Drug Intelligence Publications, Hamilton, Illinois

    Google Scholar 

  10. Waisbren BA, Hueckel TS (1950) Reduced absorption of aureomycin caused by aluminium hydroxide gel. Proc Soc Exp Biol Med 73: 73–74

    Google Scholar 

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Albengres, E., Urien, S., Tillement, J.P. et al. Interactions between smectite, a mucus stabilizer, and acidic and basic drugs. Eur J Clin Pharmacol 28, 601–605 (1985).

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Key words

  • smectite
  • phenylbutazone
  • diazepam
  • pharmacokinetics
  • drug interactions
  • drug adsorption