The influence of diuretics on the excretion and metabolism of doping agents. Part IV--Caffeine

Biopharm Drug Dispos. Mar-Apr 1988;9(2):137-45. doi: 10.1002/bod.2510090203.


The urinary excretion of caffeine in humans was followed over a period of 36 h after the oral administration of ANIMINE, a formulation containing caffeine-alpha-naphthylacetate. The excretion of caffeine was not as markedly affected by the urinary pH as was found with stimulant amines. Excretion peaks were obtained 1-2 h after the ingestion and the total amount of unchanged caffeine excreted during 12 h varied from 0.57 to 1.51 per cent. The ingestion of the diuretics acetazolamide or furosemide 2 h after caffeine resulted in a urine-flow dependent and consequently increased caffeine excretion during 2-4 h post-diuretic. This increase paralleled the increase in urine volume resulting in no meaningful differences in caffeine concentration compared to normal conditions.

MeSH terms

  • Acetazolamide / pharmacology*
  • Caffeine / administration & dosage
  • Caffeine / urine*
  • Doping in Sports*
  • Furosemide / pharmacology*
  • Humans
  • Naphthols / administration & dosage


  • Naphthols
  • Caffeine
  • Furosemide
  • alpha-naphthyl acetate
  • Acetazolamide