Pharmacokinetics of 4-aminopyridine in cattle

Concentrations of 4-aminopyridine hydrochloride in plasma of cattle were measured over an 8-hour period following a bolus IV injection (0.3 mg/kg). The drug was assayed by a gas-liquid chromatographic method using a nitrogen-phosphorus detector. Plasma 4-aminopyridine hydrochloride vs time data best fit a 2-compartment pharmacokinetic model. Distribution half-life was 12.08 minutes; elimination half-life, 128.96 minutes; volume of the central compartment, 1.48 L/kg; volume of distribution based on total area, 3.07 L/kg; volume of distribution at steady state, 2.75 L/kg; and body clearance, 16.57 ml/min/kg.