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

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

This test measures a protein called C-reactive protein (CRP) in your blood. CRP is a marker that helps your body detect inflammation, which can occur due to infections, injuries, or other health conditions.

Quick summary

["CRP helps doctors track inflammation levels in your body."]

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

Key facts at a glance

LOINC
47402-3
Short code
CV2 Ab SerPl Ql IB
Synonyms
CV2 Ab SerPl Ql IB
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
ib
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 monitor inflammation in conditions like arthritis, heart disease, or infections. It can also help check for signs of inflammation after surgery or during treatment for certain illnesses.

What to Expect Before the Test

No special preparation is needed for this test. You may have a small needle inserted into your arm to draw blood. If you’re on blood thinners, let your provider know before the test.

What the Results Mean

Higher CRP levels may indicate inflammation, while lower levels suggest less inflammation. Your results will be compared to a reference range specific to your lab and health status.

Common Conditions Monitored

This test is often used to assess inflammation in conditions like rheumatoid arthritis, heart disease, or infections. It can also help evaluate responses to treatments or monitor chronic illnesses.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

CRP is a useful marker because it rises quickly in response to inflammation, making it helpful for early detection and management of certain health issues. However, it’s not specific to any single condition and can be influenced by factors like age, sex, and medications.

Short name

hsCRP

Frequently asked questions

What causes CRP levels to change?
CRP levels can rise due to infections (like colds or flu), injuries, surgeries, or certain medical conditions (like autoimmune diseases). They may also be affected by factors like stress, smoking, or certain medications.
How often should I get this test?
Your healthcare provider will determine how often you need this test based on your health needs. Some people get it yearly, while others may need it more often if they have ongoing health concerns.
Can CRP levels be affected by diet or lifestyle?
Yes, lifestyle factors like diet, exercise, and smoking can influence CRP levels. Eating a healthy diet, staying active, and avoiding smoking may help lower inflammation.
  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