Intravenous Administration

Definition

Intravenous (IV) administration is a parenteral delivery route in which a compound is injected directly into the venous system, providing immediate entry into systemic circulation without an absorption phase. Because IV administration bypasses absorption entirely, bioavailability is defined as 100% and is used as the reference standard against which other routes are compared. In preclinical animal research, IV administration provides the most controlled and reproducible systemic exposure, making it the gold standard route for pharmacokinetic parameter determination. Common IV administration sites in rodent research include the tail vein, jugular vein, and femoral vein.

Research Context

Intravenous administration is used in preclinical peptide research primarily for pharmacokinetic studies, where precise control of compound exposure is needed to accurately calculate clearance, volume of distribution, and bioavailability. IV pharmacokinetic studies establish reference parameters for comparison with other administration routes. In studies examining rapid receptor engagement or time-sensitive biological effects, IV administration ensures that the compound reaches target tissues with minimal delay. Published IV pharmacokinetic data for research peptides is used to calculate bioavailability estimates for other routes.