ISSN:
1573-8744
Keywords:
intravenous hydrocortisone
;
blood concentrations
;
pharmacokinetics
;
endogenous hydrocortisone suppression
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract The pharmacokinetics of hydrocortisone were examined following single intravenous doses of 5, 10, 20, and 40 mg hydrocortisone, as the sodium succinate salt, to healthy male volunteers. Endogenous hydrocortisone was suppressed by administration of 2 mg dexamethasone the night before hydrocortisone injection. Plasma samples obtained serially during 8 h after hydrocortisone injection were assayed by reversephase HPLC using a fixed wavelength (254 nm) ultraviolet detector. Initial concentrations of hydrocortisone in plasma were proportional to dose size. The subsequent decline in hydrocortisone concentrations was biphasic, and individual data sets were adequately described in terms of the pharmacokinetic two-compartment open model. Values of pharmacokinetic parameters were similar from the 5, 10, and 20 mg doses. Following the 40 mg dose, the overall elimination rate constant decreased, while the distribution volume, Vdss,and plasma clearance increased, in comparison with the values obtained from lower doses. Changes in the pharmacokinetics of hydrocortisone at high doses may be related to drug concentrationdependent changes in the binding of hydrocortisone to plasma proteins. Previously reported dosedependent changes in some pharmacokinetic parameters following oral hydrocortisone are attributed to absorption rather than distribution or elimination effects.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01062332
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