Aminopyrine disposition: studies on breath, saliva, and urine of normal subjects and patients with liver disease.

To investigate aminopyrine disposition, breath, saliva, and urine were collected from 25 control patients, 15 patients with hepatocellular disease, and 26 patients with hepatic neoplasm after oral administration of 2 muCi [14C]aminopyrine. The percentage 14C excreted in breath 14CO2 in 2 hr (aminopyrine breath test, ABT) correlated with the breath 14CO2 elimination rate (r = 0.92, p less than 0.01), with the aminopyrine metabolic clearance rate (MCR) (r = 0.85, p less than 0.01), and with the plasma half-life of 4-aminoantipyrine (r = -0.54, p less than 0.05). The ABT permits study of aminopyrine disposition with simplicity, accuracy, and safety.