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C-reactive protein, serum/plasma concentration (high-sensitivity)

Published: August 9, 2026Updated: August 16, 2026

This test measures the level of a protein called C-reactive protein (CRP) in your blood. CRP is produced by your liver in response to inflammation.

Quick summary

["CRP helps doctors assess inflammation, which can signal underlying health issues."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
9979-6
Short code
QRS T-Amp L-V1
Synonyms
QRS T-Amp L-V1
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
ekg
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 Is This Test Done?

Your healthcare provider may order this test to check for signs of inflammation in your body. High CRP levels can be linked to conditions like infections, autoimmune diseases, or heart disease. It may also be used to monitor treatment progress for certain conditions.

What to Expect Before the Test

No special preparation is usually needed. You may have blood drawn from a vein in your arm, similar to other blood tests. If you’re on blood thinners, inform your doctor beforehand.

What the Results Mean

Results are not given as a single number range but are compared to your baseline or clinical context. Elevated levels may indicate inflammation, while normal levels suggest low inflammation. Your doctor will interpret results in relation to your health status.

Common Conditions Monitored

High-sensitivity CRP is often used to evaluate risk for cardiovascular diseases, track inflammatory conditions like rheumatoid arthritis, or monitor responses to treatments for infections or autoimmune disorders.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

CRP is a marker of systemic inflammation. While it doesn’t diagnose specific conditions, it helps guide decisions about further testing or treatment adjustments. Always discuss results with your healthcare provider.

Short name

hs-CRP

Frequently asked questions

What causes CRP levels to rise?
CRP levels can increase due to infections (like pneumonia or urinary tract infections), injuries, surgeries, or certain medications. Chronic conditions such as arthritis or heart disease may also lead to higher CRP levels over time.
Can CRP levels be affected by diet or exercise?
Diet and exercise can influence inflammation indirectly. For example, a healthy diet rich in fruits and vegetables may support lower CRP levels, while certain processed foods or obesity may raise them. However, CRP itself is not directly affected by diet or exercise alone.
How often should CRP be checked?
The frequency depends on your medical condition and treatment plan. Your doctor may recommend periodic checks if you have a chronic inflammatory disease, heart risk factors, or are undergoing treatment for an ongoing condition.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

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.

Medical Disclaimer

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