Erythrocyte Sedimentation Rate (ESR)

A non-specific inflammation marker that moves over days rather than hours, so it shows a pattern where hs-CRP shows a moment.

Erythrocyte Sedimentation Rate in the Biomarker Guide — what it is, why it is tested, and what moves the number.

Add-on markers can only be added to venous samples.

This marker sits outside the lab’s UKAS ISO 15189 scope. Same lab, same analysers — see Turnaround Times for what that means.

Timing

No fasting needed and no particular time of day. Recent illness is what matters. ESR stays raised for weeks after an infection, so a sample taken soon after one tells you about the infection rather than about your baseline.

Turnaround: the lab reports this test within 24 hours of receiving your sample, counted in working days. Most samples reach them within about 3 days of posting. Full detail on our Turnaround Times page.

We do not interpret results. Not medical advice or a diagnosis.