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Immunology & Serology Home collection available

Complement C3 & C4

Profile2 tests included
SampleBlood
FastingNot required
Report in24-48 hrs

Tests included in this profile 2

How to prepare

No fasting needed

You can eat and drink normally before the test.

Good to know

No special preparation needed.

Medicines

Tell our phlebotomist about any medicines you take. Don't stop them without asking your doctor.

Comfortable clothes

Wear a loose sleeve so the sample can be taken easily from your arm.

How it works

Book onlinePick a time slot
Home visitSealed, sterile kit
Lab testingBarcode tracked
ReportIn 24-48 hrs

About this test

C3 and C4 are proteins of the complement system, which helps antibodies destroy germs. In some autoimmune diseases, especially lupus, these proteins are used up and their levels drop.

Why is this test done?

  • Monitor lupus activity
  • Look into kidney inflammation (glomerulonephritis)
  • Investigate repeated infections or swelling attacks

Symptoms — when should you get tested?

  • Joint pain and rash
  • Swelling of face or legs
  • Foamy or red urine
  • Repeated infections

Normal range

C3 90 – 180 mg/dL
C4 10 – 40 mg/dL

Reference ranges differ slightly between labs, methods, age and sex. Always discuss your report with your doctor.

If your result is high

High C3 and C4 are seen during inflammation and infections, as they are acute-phase proteins.

Common reasons
  • Acute infection or inflammation
  • Some cancers

If your result is low

Low C3 or C4 suggests the complement system is being used up by immune activity.

Common reasons
  • Active lupus
  • Some kidney diseases
  • Severe infection
  • Inherited complement deficiency or hereditary angioedema (low C4)

How is the test done?

  1. 1
    Book online

    Choose your slot for home collection or a visit to our centre.

  2. 2
    Blood sample taken

    A trained phlebotomist takes a small blood sample from a vein in your arm with a sealed, single-use needle. It takes about 2 minutes.

  3. 3
    Tested in our lab

    Your barcoded sample is tested on automated machines with strict quality checks.

  4. 4
    Report on WhatsApp

    A pathologist checks the result and the report reaches you on WhatsApp and email.

Frequently asked questions

No fasting is needed for this test. You can eat and drink normally.

Your report is usually ready in 24-48 hrs after the sample reaches our lab. We send it on WhatsApp and email, and you can also download it from the Reports page.

Please call our team to confirm whether home sample collection is available for your location and test.

This test needs a blood sample. No special preparation needed.

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