Abstract
The in vivorate of biodegradation of dipotassium clorazepate to N-desmethyldiazepam in humans was shown to decrease with an increase in gastric pH. When gastric pH was maintained above 6 for 2 hr with sodium bicarbonate, the bioavailability of intact clorazepate, as determined by evaluating its conversion and absorption as N-desmethyldiazepam, was reduced from 5% to 75% when compared in the same subject with gastric pH less than 3. The corresponding N-desmethyldiazepam blood level maxima occurred later in time and were only 14–46% of the levels achieved from an acidic stomach. These findings indicate that the pH of the stomach can influence the absorption of dipotassium clorazepate.
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Abruzzo, C.W., Macasieb, T., Weinfeld, R. et al. Changes in the oral absorption characteristics in man of dipotassium clorazepate at normal and elevated gastricpH. Journal of Pharmacokinetics and Biopharmaceutics 5, 377–390 (1977). https://doi.org/10.1007/BF01061697
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DOI: https://doi.org/10.1007/BF01061697