Skip to content

C-reactive protein (CRP) concentration, serum/plasma

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

This test measures the level of C-reactive protein in your blood, a substance produced by your liver in response to inflammation or infection.

Quick summary

["CRP helps doctors assess inflammation and guide treatment decisions."]

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

Key facts at a glance

LOINC
10860-5
Short code
VZV Spec Ql Cult
Synonyms
VZV Spec Ql Cult
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
organism-specific-culture
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 CRP Matters in Your Health

CRP is often checked when you have symptoms like fever, pain, or swelling, or if you’re at higher risk for conditions like heart disease or autoimmune disorders. It’s also used to monitor how well certain treatments are working.

What Could Trigger High CRP Levels?

Elevated CRP can signal infections (like pneumonia or urinary tract infections), injuries, or inflammatory diseases (such as rheumatoid arthritis). It may also rise after surgery or during certain cancers.

How Is CRP Tested?

Your blood is drawn, and the CRP level is measured using an immunoassay method, which detects the protein’s presence and concentration.

What Do Results Mean?

Results are interpreted by your healthcare provider based on your symptoms, medical history, and other tests. Very high levels may require further investigation.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

CRP

Frequently asked questions

What if my CRP is high?
A high CRP may mean you have an infection, inflammation, or another underlying issue. Your doctor will discuss next steps, such as additional tests or treatments.
How often should I get this test?
Your doctor will determine how often you need CRP testing based on your health needs, such as monitoring chronic conditions or responding to symptoms.
Can diet or exercise affect CRP levels?
Yes, lifestyle factors like diet, exercise, and stress can influence inflammation. Eating anti-inflammatory foods, managing weight, and reducing stress may help lower CRP levels over time.
  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