Histidine concentration in serum/plasma
This test measures the amount of histidine, an essential amino acid, present in your blood. Histidine helps produce important proteins and supports healthy skin, hair, and red blood cells.
["Histidine levels can help assess amino acid metabolism and may be checked in conditions affecting protein synthesis or amino acid disorders."]
Key facts at a glance
- LOINC
- 47646-5
- Short code
- Histidine SFr Amn
- Synonyms
- Histidine SFr Amn
- Category
- chemistry
- Sample
- fluid
- Container
- Sterile tube
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Specimen volume
- 2-5 mL
- Stability
- Room temperature: 2h, Refrigerated: 24h
- Hemolysis max
- 300
- TAT
- 4–24 hours
- Order
- routine
Why Might This Test Be Ordered?
Your healthcare provider may order this test if you have symptoms or conditions linked to amino acid imbalances, such as genetic disorders affecting metabolism, liver disease, or kidney problems. It may also be part of a broader evaluation for nutritional deficiencies or unexplained fatigue.
What Does This Test Involve?
A blood sample is taken from a vein, usually in your arm. The sample is then sent to a lab where histidine levels are measured using a specialized analytical method, often an immunoassay or similar technique.
What Are Common Causes of Abnormal Results?
Low levels of histidine might be seen in conditions that impair protein synthesis, such as severe liver disease or certain genetic metabolic disorders. High levels could indicate overproduction of histidine, though this is less common and may relate to specific medical conditions or medications.
How Is This Test Performed?
The test involves collecting blood from a vein. The sample is processed and analyzed to determine the concentration of histidine in your serum or plasma.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Histidine Level
Frequently asked questions
Histidine is a building block for proteins and plays a role in the production of histamine, which is involved in immune responses and digestion. While histidine itself is not directly linked to major health conditions, abnormal levels may indicate underlying metabolic or systemic issues that require further evaluation by a healthcare provider.
A low histidine level may suggest an underlying condition affecting amino acid metabolism, such as a genetic disorder or severe liver/kidney dysfunction. It could also be part of a broader nutritional assessment if you have symptoms like fatigue, weakness, or unexplained weight changes.
Results are typically available within 1 to 3 business days, depending on your lab’s processing schedule. Your healthcare provider will discuss the results with you during your follow-up visit.
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