Paracetamol disposition in renal allograft recipients

Objective: To evaluate the disposition of paracetamol in renal allograft recipients. Method: Eight fasting renal allograft recipients were given 1 g soluble paracetamol orally. Results: Paracetamol was absorbed rapidly, and the mean plasma half-life from 2 h to 8 h was 2.6 +/- 0.5 h. After that, disappearance of paracetamol from the plasma was slower. Both the glucuronide and sulphate conjugates of paracetamol had slow elimination half-lives of 15.1 +/- 8.8 h and 26.2 +/- 14.6 h, and there were residual amounts of both conjugates in the plasma at 24 h. The renal clearances of both conjugates were low (21 +/- 14.2 ml/min and 32.4 +/- 31.4 ml/min) and there was a significant negative correlation between total amount of paracetamol recovered in the urine in 24 h and serum creatinine (r=-0.89, P<0.01). Conclusion: Paracetamol disposition is abnormal in renal allograft recipients and seems to relate to abnormal renal function in these patients.