Which is the most appropriate baseline test prior to initiation and monitored regularly during methotrexate treatment?

• A. Creatinine clearance
• B. Fasting lipid panel
• C. Liver function tests
• D. Haemoglobin A1c

Answer: (C)

Methotrexate can cause liver injury, so checking liver function before starting and monitoring it regularly during treatment directly targets the organ most at risk. Baseline liver function tests establish the liver’s existing status and provide a reference to detect any hepatotoxic changes early, such as rising AST/ALT or bilirubin, which can prompt dose adjustments or discontinuation to prevent permanent damage. While renal function is also important to monitor because MTX is cleared by the kidneys, liver function monitoring best addresses the primary safety concern with this drug. Lipid panels and HbA1c don’t relate to MTX safety in the same way.