Glutathione Peroxidase Activity in Serum/Plasma
This test measures the activity level of glutathione peroxidase, an enzyme that helps protect cells from oxidative damage caused by free radicals.
["Glutathione peroxidase helps your body defend against harmful molecules that can damage cells."]
Key facts at a glance
- LOINC
- 17858-2
- Short code
- GGT Fld-cCnc
- Synonyms
- GGT Fld-cCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 8
- Ref high
- 61
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 82977
- SNOMED
- 3110003
- 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
Why This Test Might Be Ordered
Your healthcare provider may recommend this test if you have symptoms of oxidative stress, such as chronic fatigue, muscle weakness, or conditions linked to oxidative damage like certain autoimmune diseases or metabolic disorders. It may also be used in research or specialized clinical settings to assess antioxidant capacity.
What to Expect Before the Test
No special preparation is typically required, but you may be asked to fast for a few hours before the blood draw if your provider specifies it. Avoid smoking or consuming alcohol for a certain period before testing, as these can affect enzyme activity.
What Happens During the Test
A healthcare professional will draw blood from a vein in your arm. The blood sample will be sent to a lab to measure the enzyme activity level. The process usually takes a few minutes.
Results and Interpretation
Results are reported as enzyme activity levels, which may be compared to a reference range if available. Your provider will discuss the results with you, considering your overall health and symptoms.
Reference range
Adult males: 8-61 U/L; Adult females: 5-36 U/LN/A
No special preparation required. Avoid fatty meals before the test if possible.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Glutathione Peroxidase (GPX) Activity
Frequently asked questions
Glutathione peroxidase plays a critical role in maintaining cellular health by neutralizing harmful peroxides. Low activity may suggest oxidative stress or deficiencies in antioxidant defenses, potentially linked to chronic diseases or certain genetic conditions. High activity could indicate a compensatory response to oxidative challenges.
A low activity level may indicate increased oxidative stress in your body, which can be associated with conditions like chronic fatigue syndrome, certain autoimmune diseases, or metabolic disorders. Your provider may explore further testing or treatments to address underlying causes, such as dietary adjustments or antioxidant support.
High activity might suggest your body is responding to oxidative damage, possibly due to chronic exposure to environmental toxins, certain medications, or pre-existing health conditions. It’s important to discuss these findings with your healthcare provider to determine if further evaluation is needed.
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 16, 2026. · Read our editorial policy