Multiple dose activated charcoal versus hemodialysis in the management of theophylline overdose: a toxicokinetic-based comparison

ABSTRACT

Thirty patients with theophylline overdose were selected to study the toxicokinetics of theophylline during intestinal dialysis using multiple-dose activated charcoal [MDAC] and during continuous hemodialysis. Patients were classified according to serum theophylline level [STL] into two groups. Group [I] comprised 20 patients with a mean STL of 43.29 +/- 15, 02. Treatment in this group was started using MDAC. Group [II] comprised 10 patients with a mean STL of 81.32 +/- 31.07. Treatment in this group was started using continuous hemodialysis up to vomiting control, then continued using MDAC in the same regimen as group [I]. The enhanced elimination procedures in the two groups were initiated 2 hours post-admission. STL peaked at 3 hours, for both groups [1 hour after initiating the enhanced procedure]. Greater variation in STL among patients in each time interval in the hemodialysis group was clear compared to MDAC group. Following the peak, serum theophylline concentrations, in each treatment group, declined in a biphasic linear fashion. Non significant difference was observed in the pharmacokinetic parameters of theophylline as a result of MDAC; either from the start or following hemodialysis. Elimination rate constant [Ke], elimination half life [t1/2] and total body clearance of theophylline were 0.168 +/- 0.033 hour[-] 1, 4.125 +/- 1.56 hour, and 0.0841 + 0.028 L/kg/ hr, respectively as a result of MDAC modality from the start and 0.186 +/- 0.048 hour[-1], 3.73 +/- 1.087 hour, and 0.093 + 0.031 L/kgl hour, respectively following. hemodialysis. Compared with MDAC, hemodialysis did not significantly increase Elimination rate constant [Ke] of theophylline and consequently did not shorten its elimination half life [t1/2] or increase its clearance significantly. In conclusion, hemodialysis showed no advantages over MDAC in enhancing theophylline elimination in overdose except that it could be used in patients with protracted vomiting