Effect of Hepatic Disease on Pharmacokinetics: Pathophysiologic Assessment and Liver Function Test

In clinical practice, directly measuring hepatic blood flow to assess liver function is often impractical due to the specialized techniques required.

Instead, clinicians estimate hepatic function through patient examination and liver function tests.

The Child–Pugh and MELD help evaluate hepatic impairment but don't directly correlate with drug pharmacokinetics.

Chronic liver disease affects drug metabolism and clearance, necessitating a tailored risk assessment before dosing.

Dosing for hepatically impaired patients remains an area of ongoing development. However, drug markers such as aminotransferases, alkaline phosphatase, bilirubin, and prothrombin time provide valuable insights into hepatic function.

For instance, elevated AST/ALT ratios suggest acute liver injury, alcoholic hepatitis, or advanced liver fibrosis, while increased AP levels may indicate hepatic tumors or biliary obstruction.

Additionally, deviations in urinary bilirubin levels and prothrombin time can help diagnose hepatobiliary disease and hepatic failure, respectively.