ALT (Alanine Aminotransferase)

The most liver-specific enzyme marker — your primary hepatotoxicity signal.

What it is

ALT is primarily found in the liver. When liver cells are damaged or inflamed, ALT is released into the blood. It is more liver-specific than AST and is the primary marker for monitoring liver health.

Why it matters

During chemotherapy, ALT is one of the first markers to rise when the liver is under stress. Sustained elevation can require dose modification or treatment pause. Tracking it through cycles lets you discuss trends with your oncologist proactively.

How to test

Standard liver function blood panel.

This information is for educational purposes only. Always discuss testing and interpretation of results with your care team.

Optimal range

Below 41 U/L (men) / 31 U/L (women)

normal

Above 3× upper limit

clinically significant elevation

How often

Every cycle during chemotherapy. Every 6–12 weeks otherwise.