Comparison of dexamethasone pharmacokinetics in female rats after intravenous and intramuscular administration
Related Experiment Video
Updated: Jul 29, 2026

Manual Restraint and Common Compound Administration Routes in Mice and Rats
Published on: September 26, 2012
Mahesh N Samtani1, William J Jusko
1Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, State University of New York, Buffalo, New York 14260, USA.
Abstract:
This study seeks a route of drug administration that would produce a pharmacokinetic profile for dexamethasone not significantly different from the intravenous route in female rats and would offer reproducible drug input with minimal stress to the animals. The intramuscular (i.m.) route of drug administration vs intravenous (i.v.) injection were compared in three female Wistar rats administered 1 mg/kg dexamethasone phosphate. Dexamethasone plasma concentrations were measured by a normal phase HPLC assay for 12 h after drug administration. Dexamethasone exhibited monoexponential behavior after intravenous dosing and was absorbed rapidly after intramuscular dosing (absorption half-life of 14 min) with 86% bioavailability. Dexamethasone had a terminal half-life of 2.3 h after drug administration by either route. The volume of distribution of 0.78 l/kg and the clearance of 0.23 l/h/kg are in good agreement with reported pharmacokinetic parameters in male rats. Intravenous dosing can be replaced by intramuscular dosing without causing any marked difference in dexamethasone pharmacokinetics.
Related Concept Videos
Routes of Drug Administration: Parenteral
The intravenous route (IV) of drug administration can be further categorized into two types. The bolus injection administers the entire dose rapidly, while an intravenous infusion slowly delivers smaller doses steadily.
The IV route is often...
Compartment Models: Two-Compartment Model
Nonlinear Pharmacokinetics: Drug Elimination for IV Bolus Injection
Following the administration of a single intravenous (IV) bolus injection, we can determine the concentration of the drug in the plasma at any given time. This calculation is achieved using a specific equation that integrates the values of Vmax and KM.
We can also...
Drug Accumulation During Multiple Dosing: Repetitive IV Injections
Determination of Multiple Dosing Parameters: Loading and Maintenance Doses
Pharmacokinetic–Pharmacodynamic Relationship: Duration of Dose-Effect Relationship

