Abstract
Clonazepam (1 mg/kg) and antipyrine (0.1 mg/kg) were administered simultaneously by intravenous bolus injection to three dogs. After 2 weeks of chronic phenobarbital administration, the studies were repeated. Plasma concentration-time curves in all studies were biexponential. Phenobarbital administration increased total plasma clearances of clonazepam and antipyrine by 102% and 98.5%, respectively. Volumes of distribution were not altered, and consequently reductions in terminal exponential half-lives observed after phenobarbital were attributed to increases in clearances.
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Bekersky, I., Maggio, A.C., Mattaliano, V. et al. Influence of phenobarbital on the disposition of clonazepam and antipyrine in the dog. Journal of Pharmacokinetics and Biopharmaceutics 5, 507–512 (1977). https://doi.org/10.1007/BF01061731
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DOI: https://doi.org/10.1007/BF01061731