Medyra
Immune System

Reviewed: 13. Juli 2026

C3 Complement C3

Unit: g/l

Quick Explanation

Complement factor C3 is part of a system that directly fights pathogens and supports inflammatory reactions. Low values can indicate increased consumption with autoimmune diseases like lupus, elevated values occur with acute inflammation.

📊 Reference Values

Low
below 0.9 g/l
Normal
0.9 – 1.8 g/l
Elevated
above 1.8 g/l

ℹ️ Reference ranges may vary slightly between laboratories. Always compare your value with the reference range from your own lab report.

🔍 Possible Causes

Value too high — possible causes

  • ·Acute inflammation or infection

Value too low — possible causes

  • ·Autoimmune diseases (e.g. systemic lupus erythematosus)
  • ·Congenital complement deficiency
  • ·Chronic liver disease

This list shows possible causes — not a diagnosis. Only your doctor can correctly interpret your result.

🩺 Questions for Your Doctor

  • Does my low C3 value indicate an autoimmune disease?
  • Should C4 and ANA also be measured?

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Medical Disclaimer

The content on this page is for general information only and does not replace professional medical advice, diagnosis, or treatment. Always consult your doctor or pharmacist for health-related questions. Lab values should always be assessed in the context of your personal medical history.

Complement C3 explained | Medyra | Medyra AI