Summary
We have studied the pharmacokinetics of the anti-mycotic ketoconazole in seven patients who took it for 1–6 months at a dose of 200 mg daily.
The mean elimination half-life of the drug was 3.3 h, and although the ketoconazole was given only once daily, a satisfactory clinical response was obtained in all seven individuals. Only a small fraction of the absorbed drug (mean 0.22%) was excreted unchanged in the urine, suggesting almost complete metabolism.
Our results support the concept that anti-mycotic activity in the tissues continues after the plasma drug concentration has fallen below a critical level. Our results also support the concept of a change in pharmacokinetics with chronic dosing.
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Badcock, N.R., Bartholomeusz, F.D., Frewin, D.B. et al. The pharmacokinetics of ketoconazole after chronic administration in adults. Eur J Clin Pharmacol 33, 531–534 (1987). https://doi.org/10.1007/BF00544251
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DOI: https://doi.org/10.1007/BF00544251