Serum or Plasma Free Fructosamine (Substance Concentration)
This test measures the average blood sugar levels over the past 2 to 3 weeks by tracking glycated proteins, specifically albumin, in your serum or plasma. It provides insight into how well your blood sugar has been controlled during this period.
["Helps assess long-term blood sugar management without needing a blood draw for hemoglobin A1c."]
Key facts at a glance
- LOINC
- 12241-6
- Short code
- OF NFr RBC Diluted
- Synonyms
- OF NFr RBC Diluted
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 4.2
- Ref high
- 5.9
- Critical range
- 2 N/A – 7 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- rbcs-diluted
- CPT
- 85041
- SNOMED
- 900000000000003001
- 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 Matters for You
Free fructosamine is useful for people with diabetes or those at risk of developing it. It reflects your average blood sugar levels over time, which can help doctors adjust treatment plans. Unlike hemoglobin A1c, this test doesn’t require a long-term blood sample and can be useful in certain clinical situations where A1c results are unclear.
How the Test Works
Your healthcare provider will take a blood sample from a vein, usually in your arm. The blood is then processed to separate the serum or plasma, which is tested for fructosamine levels using an immunoassay method. This test measures the concentration of glycated albumin, indicating how your blood sugar has been influenced over time.
When You Might Need This Test
This test may be recommended if you have diabetes and your blood sugar control is difficult to assess with hemoglobin A1c. It can also be useful in patients with kidney disease or those who have had recent blood transfusions, as these conditions can affect hemoglobin A1c results.
What to Expect Before the Test
No special preparation is needed for this test. You can eat and drink normally on the day of the test. If you are on certain medications that might affect blood sugar, like insulin or oral diabetes medications, inform your healthcare provider before the test.
Reference range
Adult males: 4.2-5.9; Females: 3.8-5.1 x 10^12/LN/A
No special preparation required. Stay well hydrated.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Free fructosamine is particularly valuable for monitoring blood sugar control in patients who cannot have a hemoglobin A1c test, such as those with severe anemia or recent blood transfusions. It provides a snapshot of glycemic control over the past 2 to 3 weeks, which can help in tailoring diabetes management strategies. However, it should be used alongside other tests and clinical assessments for a comprehensive understanding of your health.
Short name
Free Fructosamine
Frequently asked questions
What does a high or low result mean?
Does this test require fasting?
How long will it take to get the results?
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