Pharmacokinetics of amoxicillin: Dosage nomogram for patients with impaired renal function

Amoxicillin pharmacokinetics after intravenous administration were studied in patients with normal renal function, with impaired renal function, and during hemodialysis. The average urinary recovery was 68% in patients with normal renal function. Serum half-life was highly correlated (r = 0.967) with creatinine clearance corrected for body weight. Expected half-life was 71 min for a corrected creatinine clearance of 100 ml/min per 70 kg and 16 h in the anephric patient. Average amoxicillin half-life on hemodialysis was 3.6 h. We present a dosage nomogram for making appropriate adjustments to loading dose based on patient weight and maintenance dose based on corrected creatinine clearance.