The effect of renal disease on the pharmacokinetics of diethylcarbamazine in man.

1 The pharmacokinetics of diethylcarbamazine (DEC) were studied in twelve patients with chronic renal function impairment. 2 Selected pharmacokinetic parameters, plasma half-life (T1/2), area under the plasma concentration-time curve (AUC), elimination rate constant (Kel) and 24 h urinary excretion were regressed versus parameters indicative of renal function. 3 Significant negative correlations were observed between creatinine clearance and both plasma T1/2 and log10 T1/2. 4 Significant positive correlations were obtained between (a) creatinine clearance and elimination rate constant of DEC and (b) reciprocal serum creatinine and l/T1/2. Creatinine clearance was significantly and positively correlated with 24 h urinary excretion of DEC. 5 No significant correlations were observed between age, sex or weight and renal function but DEC excretion did appear to decrease with increasing urinary pH. 6 Plasma half-life, and area under the plasma concentration-time curve were increased and 24 h urinary excretion of DEC was significantly reduced in patients with chronic renal function impairment, compared with normal volunteer subjects receiving an identical dosage of DEC at acidic urinary pH.