Serum Capillary Blood Hemoglobin (Capillary Blood Hemoglobin)
This test measures the amount of hemoglobin in a small sample of blood taken from a finger prick. Hemoglobin is the protein in red blood cells that carries oxygen throughout your body.
["A hemoglobin test helps check for anemia or other blood-related conditions by assessing your red blood cell function."]
Key facts at a glance
- LOINC
- 19913-3
- Short code
- Diff cap.CO Hgb adj
- Synonyms
- Diff cap.CO Hgb adj
- Category
- hematology
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 12
- Ref high
- 17.5
- Critical range
- 7 N/A – 20 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 85018
- SNOMED
- 900000000000003004
- 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 Is Done
Your healthcare provider may order this test if you have symptoms like fatigue, pale skin, or shortness of breath, which can indicate low hemoglobin levels. It may also be part of routine blood work or screening for conditions like anemia or blood disorders.
What to Expect Before the Test
You can eat and drink normally before this test. No special preparation is needed, but inform your provider if you’re taking blood thinners or have a history of bleeding issues.
How the Test Is Performed
A healthcare professional will clean your finger and use a small needle to take a tiny drop of blood from your fingertip. The sample is then analyzed to measure hemoglobin levels.
What the Results Mean
Results are compared to standard ranges to determine if your hemoglobin is within normal limits or if further evaluation is needed. Low levels may suggest anemia or other blood disorders, while very high levels could indicate conditions like polycythemia.
Reference range
Adult males: 13.5-17.5 g/dL; Females: 12.0-16.0 g/dLN/A
No special preparation usually required. Stay well hydrated. Inform your healthcare provider of all medications and supplements you are taking.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Hemoglobin (Capillary Blood)
Frequently asked questions
What causes low hemoglobin levels?
What causes high hemoglobin levels?
How often should this test be done?
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