[One point determination of oral caffeine clearance in patients with liver diseases]. / Einpunktbestimmung der oralen Koffeinclearance bei Patienten mit Lebererkrankungen.

ABSTRACT

Caffeine clearance has been determined in 117 volunteers and patients (including 27 patients with liver cirrhosis) after oral application of 366.1 mg caffeine according to conventional pharmacokinetic methods (Cl = D/AUC). The resulting clearance values can be estimated with adequate accuracy from the plasma concentration at 12h for a concentration range of 2.0 to 6.5 mg/l according to Cl max = Doses/C 12h x t 12h x e and for concentrations higher than 6.5 mg/l according to Cl = Vd x (1n (D/Vd) - 1n C 12h/t 12h Vd is estimated from body weight as Vd = 0.42 x BW. "One - point" - estimation does not provide reliable data for plasma concentrations below 2.0 mg/l.