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Haematology Home collection available

Prothrombin Time

Parameters1 tested
SampleBlood
FastingNot required
Report inSame day

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 same day

About this test

Prothrombin Time (PT/INR) measures how long your blood takes to clot. It is used to monitor blood thinners like warfarin and to check liver function and bleeding risk.

Why is this test done?

  • Monitor warfarin (blood thinner) treatment
  • Check bleeding risk before surgery
  • Check liver function

Symptoms — when should you get tested?

  • Easy bruising or bleeding
  • Blood in urine or stool
  • Heavy periods

Normal range

PT 11 – 13.5 seconds
INR (not on blood thinners) 0.8 – 1.1
INR (on warfarin, usual target) 2.0 – 3.0

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

If your result is high

A prolonged PT/high INR means blood takes longer to clot — risk of bleeding.

Common reasons
  • Blood thinners (warfarin)
  • Liver disease
  • Vitamin K deficiency

If your result is low

A short PT is usually not significant.

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 same day 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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