C-Reactive Protein (CRP)

What is C-Reactive Protein (CRP)?

A protein made by the liver that rises in response to inflammation in the body.

CRP is made by the liver and rises within hours of infection, injury, or ongoing inflammation, then falls again once the trigger resolves — it's a general marker of inflammation, not specific to any one condition. A more sensitive version, hs-CRP (high-sensitivity CRP), can detect much lower concentrations and is used specifically to gauge cardiovascular risk in people who otherwise appear healthy.

Tests often checked alongside this

• ESR — tracks inflammation over a longer time window
• Lipid panel — adds context for cardiovascular risk
• Homocysteine — another independent marker of cardiovascular risk

How this can show up in how you look and feel

• CRP itself typically produces no noticeable symptoms or visible signs
• Elevated CRP is usually silent, which is exactly why it's tested rather than felt
• Any symptoms usually come from whatever underlying condition is driving the inflammation, not from CRP directly

What can affect this marker

• Recent infection or illness
• Intense or prolonged exercise
• Smoking and body weight
• Chronic inflammatory conditions

What to track over time

• Your trend across repeat tests
• Whether levels return to baseline
• Alongside other inflammation markers
• Symptoms during flare-ups

What to ask your doctor

• What might be driving this result?
• Should I retest once I'm well?
• Is this the high-sensitivity version?
• Does this affect my heart risk?

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