Clearance of theophylline by hemodialysis in one patient with chronic renal failure.

The clearance of theophylline by hemodialysis was determined in one patient who had polycystic kidney with chronic renal failure and bronchial asthma. The serum levels of theophylline were determined by enzymatic immunoassay on two consecutive days, once on a dialysis day and again on a nondialysis day. Clearance of theophylline by hemodialysis was 119 ml/min, and the extraction efficiency was 0.56. The elimination half-life of theophylline shortened from 5.7 h to 1.6 h during hemodialysis. The dialysis rate constant (Kd) was 0.32/h, and 79 percent of the total body store of the drug was removed during a 4-h dialysis. Patients receiving theophylline who are maintained on hemodialysis should be closely monitored for bronchospasm during and after the hemodialysis procedure. Measurement of serum concentrations of theophylline should be employed to facilitate increases in dosage during hemodialysis.