The 30-minute aminopyrine breath test: optimization of sampling times after intravenous administration of 14C-aminopyrine.

In a retrospective analysis of 78 well-defined patients, the procedure of the aminopyrine breath test was evaluated. After intravenous administration of 14C-aminopyrine (1.5 microCi, 1 mg) 14CO2 was sampled at 15-min intervals for 1 h. Samples taken at 15, 30, 45 and 60 min were similarly able to distinguish between patients with mild liver disease and patients with enzyme induction. The results of the aminopyrine breath test at each sampling time were highly correlated with the galactose elimination capacity and the fractional clearance of indocyanine green. It is concluded that sampling at 30 min represents a satisfactory compromise between practicality and accuracy of the test.