European Journal of Clinical Pharmacology

, Volume 12, Issue 3, pp 229–233 | Cite as

Dose dependence of the14C-aminopyrine breath test

Intrasubject comparison of tracer and pharmacological doses
  • Iva Gikalov
  • Johannes Bircher


Although the aminopyrine breath test has received much attention, the question has not yet been settled whether pharmacological or tracer doses of the drug should be used. Nine volunteers were given14C-aminopyrine 9 mg/kg or a tracer amount, in a randomized sequence and according to a crossover design. The specific activity of14CO2 in breath was significantly different only during the first hour. Up to the 8th hour the disappearance of14CO2 from breath was smaller after the pharmacological (28.5±SD 5.4%/h) than after the tracer dose (36.2±10.6%/h; p<0.05). The overall disappearance of14C-atoms from the subjects was significantly slower after the higher dose. In view of the smaller radiation exposure and the decreased risk of agranulocytosis, the use of a tracer dose appears preferable.

Key words

Aminopyrine metabolism 14CO2-breath test aminopyrine demethylation dose dependent metabolism physical fitness 


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Copyright information

© Springer-Verlag 1977

Authors and Affiliations

  • Iva Gikalov
    • 1
  • Johannes Bircher
    • 1
  1. 1.Department of Clinical PharmacologyUniversity of BerneBerneSwitzerland

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