Paracetamol metabolism was compared in groups of young adult (mean age 20.8 years) and elderly (mean 79.3 years) males.
Apparent oral clearance and half-life and partial metabolic clearances to the glucuronide and glutathione-derived conjugates of paracetamol were not significantly different between the two groups. However, the partial metabolic clearance to paracetamol sulphate was 23.1% lower and renal clearance of unchanged drug was 42.9% lower in the elderly compared to the young adults.
Despite the decreased clearance by these pathways, reduction in paracetamol dosage should not be necessary in the elderly.
Key words paracetamol - drug metabolism - age - sulphation - glucuronidation