Tyrosine Serum Free Fraction
This test measures the amount of tyrosine, an amino acid, that is not bound to proteins in your blood serum. It helps assess how much tyrosine is available in your circulation.
["Understanding your tyrosine levels can help identify potential metabolic or protein-related health concerns."]
Key facts at a glance
- LOINC
- 47793-5
- Short code
- Tyrosine SFr CSF
- Synonyms
- Tyrosine SFr CSF
- Category
- chemistry
- Sample
- csf
- Container
- Sterile tube
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Specimen volume
- 1-2 mL
- Stability
- Immediate analysis required, Refrigerated: 1h
- Hemolysis max
- 200
- TAT
- 4–24 hours
- Order
- routine
Why This Test Might Be Ordered
Your healthcare provider may recommend this test if they suspect conditions affecting amino acid metabolism, protein synthesis, or liver function. It could also be part of a broader evaluation for genetic disorders or metabolic diseases.
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. Bring any medications or supplements you’re currently taking to your appointment.
What the Test Involves
A healthcare professional will collect a blood sample from a vein in your arm. The blood will be processed to separate serum, which is then analyzed for tyrosine levels. The process usually takes a few minutes and is generally comfortable.
What the Results Mean
Results are compared to a reference range specific to your age, sex, and health status. Abnormal levels may indicate issues with amino acid metabolism, liver disease, or other metabolic conditions that need further evaluation.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Elevated or low tyrosine free fractions can signal underlying metabolic disorders, such as tyrosinemia or other aminoacidopathies. It may also be relevant in diagnosing or monitoring conditions affecting protein metabolism, such as liver disease or certain genetic syndromes. Always discuss your results with your healthcare provider for personalized interpretation.
Short name
Tyrosine Free Fraction in Serum
Frequently asked questions
What causes abnormal tyrosine free fraction levels?
How often should I get this test?
Can lifestyle changes affect tyrosine levels?
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