Blood counts

What does Lactate dehydrogenase (LDH) mean on a blood test?

LDH is an enzyme found in many tissues. In some cancers, a higher level can be tracked over time as one clue about activity. It is nonspecific — many everyday things can raise it — so it is read alongside other results.

Also written as

LDH
lactate dehydrogenase

Please read: This page explains general report language and cannot interpret your personal report, diagnose a condition, judge how serious a result is, or recommend treatment. Only your care team can do that.

How to read blood counts results

Blood counts and chemistry panels are snapshots of how your body is doing on the day the sample was drawn, and they shift for many everyday reasons — hydration, infection, medicines, and the timing of treatment. Most labs print a reference range and flag values as high or low, but being outside that range does not automatically mean something is wrong, just as a value inside it does not rule everything out. What usually matters most is the trend across several tests and how a number fits with how you feel. Your care team reads these values in context and will say which ones, if any, need action.

Questions to ask your care team

Which of my values are outside the normal range, and does that need action?
Is this a one-time change or a trend I should keep watching?
Should this result change the timing or dose of my treatment?
What symptoms should make me call you if this value keeps changing?

Build your own question list

Related blood counts terms

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