Relationship between total body clearance of caffeine and urine flow rate in elderly men

Biopharm Drug Dispos. 1985 Jan-Mar;6(1):51-6. doi: 10.1002/bdd.2510060107.


The total body clearance (CL), renal clearance (CLR), and nonrenal clearance (CLNR) of caffeine from plasma were determined following the intravenous administration of caffeine (4 mg kg-1) to ten healthy men (aged 66-86 years) on three separate occasions. Positive correlations were observed between CL and urine flow rate (UFR), between CLR and UFR, and between CLNR and UFR (r = 0.8947, p = 0.0002; r = 0.8832, p = 0.0003; and r = 0.8920, p = 0.0002, respectively). Previous studies have established similar relationships between CLR and UFR for caffeine and its initial dimethylxanthine metabolites; theophylline, theobromine, and paraxanthine. A relationship between CL and UFR has not been reported previously.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Aged
  • Caffeine / blood
  • Caffeine / metabolism*
  • Caffeine / urine
  • Diuresis*
  • Humans
  • Kidney / metabolism*
  • Male
  • Metabolic Clearance Rate


  • Caffeine