Hemoglobin concentration in whole blood
This test measures the amount of hemoglobin, the protein in red blood cells that carries oxygen throughout your body. It helps doctors assess your blood’s ability to carry oxygen and detect conditions like anemia.
["Hemoglobin levels indicate whether you may have anemia or other blood-related issues."]
Key facts at a glance
- LOINC
- 4603-7
- Short code
- Hgb Koln Bld Ql
- Synonyms
- Hgb Koln Bld Ql
- Category
- hematology
- Sample
- whole-blood
- Container
- Lavender-top (EDTA)
- 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
- 3 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
Why This Test Matters
Hemoglobin levels are crucial for diagnosing and monitoring conditions such as anemia, which can cause fatigue, weakness, or pale skin. They also help identify blood loss, poor nutrition, or other underlying health problems.
What to Expect During the Test
A simple blood draw is typically used to collect this sample. You may feel a slight pinch, but it usually takes only a few minutes. No special preparation is needed unless your doctor instructs otherwise.
Common Conditions Monitored
Doctors often check hemoglobin levels during routine blood work, before surgeries, or if you have symptoms like extreme tiredness, shortness of breath, or unusual pale skin. It can also be used to track treatment progress for conditions like iron deficiency.
Factors That Can Affect Results
Several factors, such as recent blood loss, dehydration, certain medications, or chronic illnesses, can influence hemoglobin levels. If you’re unsure about your diet, recent illnesses, or medications, discuss these with your doctor.
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 (Hgb) Level
Frequently asked questions
What does a low hemoglobin level mean?
How often should I get this test?
Can diet affect my hemoglobin 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