Lactate Dehydrogenase (LDH) Activity in Serum/Plasma
This test measures the activity of an enzyme called lactate dehydrogenase (LDH), which plays a key role in energy production in your body. It helps assess conditions affecting cells, such as damage or disease.
["LDH helps identify cell damage or disease in your body."]
Key facts at a glance
- LOINC
- 108826-9
- Short code
- LDH Msmt SerPl
- Synonyms
- LDH Msmt SerPl
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 140
- Ref high
- 280
- Critical range
- — – 1000 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 83615
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What Does LDH Measure?
LDH is an enzyme found in many tissues, including the heart, liver, muscles, kidneys, and red blood cells. When cells are damaged (e.g., due to injury, infection, or certain diseases), LDH is released into the bloodstream. Measuring LDH helps doctors evaluate conditions like heart attacks, liver disease, muscle injuries, anemia, or certain cancers.
Why Might Your Doctor Order This Test?
Your doctor may order LDH testing if you have symptoms like fatigue, muscle pain, shortness of breath, or unexplained lab abnormalities. It’s also used to monitor conditions like liver disease, heart attacks, or to check for hidden cancers.
Common Conditions Linked to Elevated LDH Levels
High LDH levels may signal cell damage or disease, such as: - Heart attacks (myocardial infarction) - Liver disease (e.g., hepatitis, cirrhosis) - Muscle injuries or disorders (e.g., rhabdomyolysis) - Certain cancers (e.g., lymphoma, leukemia) - Anemia or blood disorders - Infections or severe illnesses
What Does a Low LDH Level Indicate?
Low LDH levels are less common but may occur in rare cases, such as: - Severe dehydration - Certain genetic disorders - Overproduction of red blood cells (polycythemia)
Reference range
Adult: 140-280 U/LN/A
No special preparation required. Inform provider of any chest pain or symptoms.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance: LDH’s Role in Diagnosis and Monitoring
Short name
LDH Activity
Frequently asked questions
How Often Will I Need This Test?
What Are the Possible Side Effects of This Test?
Can I Eat or Drink Before the Test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 17, 2026. · Read our editorial policy