Value of the 14C-aminophenazone respiratory test: Inhibition of the demethylation function of the liver by cimetidine

In 15 patients with healthy liver and peptic ulcer the demethylation capacity of the liver was determined by the 14C-aminophenazone breathing test before and during treatment with the H2 antagonist cimetidine (daily dose 1.0 g) measuring the expired 14CO2 (DPM/mmol CO2/70 kg body weight) before and 1 hour after intake. Influenced by cimetidine the mean 14CO2 value of 724.7 DPM (S.D. 127.7) decreased to 404.1 DPM (S.D. 153.1). The enzyme activities (ALAT, ASAT, AP, AAP, GGT, CHE) and the concentrations of serum bilirubin and serum albumin remained unchanged and did not correlate mutually and with the 14CO2 data. The aminophenazone test proved to be suitable technique for the recognition of disturbances of the MFO system. (author)