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Finger prick lancet
How-to guide

Take your blood sample with a finger prick device

What's covered?
Last reviewed: 30th July 2025
Step-by-step instructions
01Prepare your kit
Get the equipment ready
  1. Lay your kit out on a table lower than your elbow

    Do this on a low table – so your hand can be below your elbow during the test.

  2. Read the printed instructions in your kit

    Read the printed instructions in your kit
This guide is here to take you step-by-step through the process of taking a sample quickly and easily. Before you start, make sure to read the printed instructions that come with your kit. They include important health and safety information, including any risks.

  3. If your kit has a RED tube check your emails (and spam folder), you may have more instructions from us.

  4. Get a clean tissue and a clean towel
  5. Fill a large bowel with warm water

    Around the temperature you'd have in a bath.

Set up your tube(s)
    If you have a colour vision deficiency

    Please ask someone to help you identify the colours of your tube(s)

  1. Remove the cap from the first tube
  2. If your kit has 2 collection tubes, the YELLOW tube should be used first and the PURPLE tube should be used last.

  3. Stand this tube in your kit using the hole inside the box

    Keep the cap next to the tube so you remember which colour it is.

  4. Wash your hands with soap and warm water for 20 seconds

    Dry with a clean towel.

Get your blood flowing
  1. Put your whole non-dominant hand in the warm water for 2–3 minutes

    Do this for 2-3 minutes – until your fingers are slightly dimpled. Then dry with a clean towel.

  2. Get your heart rate up

    For 1 minute:

    • do some jumping jacks or swing your arm—if it’s safe for you to do so
    • clench and unclench your fists
02Collect your sample

Before you get started collecting, take care to:

  • Stand up for the whole process
    If it's safe for you to do so, as gravity helps your blood to flow.
  • Keep the tube on a low table, so your arm hangs completely straight
  • Lie down and raise your legs if you feel faint
    If you continue to feel unwell seek medical advice.
Prepare your hand
  1. Clean the ring finger with an alcohol wipe
  2. If you can’t use your ring finger

    Don’t use your little finger and avoid your thumb. Don’t use a finger if it’s hot, red or swollen. If you've had a mastectomy, use the opposite hand for the finger-prick test.

  3. Take the cap off the lancet
  4. Place the palm of your hand up on the table
Prick your finger
  1. Press the lancet down on the outer centre of your fingertip

    Do this until you hear a click. You can only use each lancet once.

  2. Wipe away the first drop of blood with a clean tissue
Fill your tube(s)
  1. Massage down your whole hand every 3-4 seconds

    Go to just before the prick — squeezing too close damages the blood.

  2. Cant get enough blood?

    If your blood stops flowing, wipe your finger with the tissue while applying pressure to get it flowing again.
    If this doesn’t work, go back through the steps above to get your blood flowing.

  3. Tap the blood into the correct tube
  4. Yellow tube

    Fill first to the top line - marked 600 or 0.8.

    Red tube

    Fill to the top line - marked 500.

    Purple tube

    Fill last, to the top line - marked 250.

    If you can't manage to fill the tube(s)

    If any of your tubes aren’t full (whether it’s one or both), unfortunately, we won’t be able to process them. Please dispose of them and drop us a message at hello@thriva.co. We’ll send you a replacement kit, completely free of charge.

Close the tube(s)
  1. Place the correct coloured cap onto the tube(s) and push down until you hear a click
  2. If bleeding doesn't stop (rare cases)

    Apply firm pressure to the wound site and raise your arm. If this doesn’t work, seek medical advice.

  3. Clean your finger with the cleansing wipe and apply a plaster (if you are not allergic)
Mix your tube(s)
  1. Mix your tubes in the order below:
    • Mix the purple tube first

      Swirl tube slowly for 20 seconds, ensuring the blood touches the sides of the tube. Your blood will remain liquid.

    • Mix the yellow tube next

      Turn it upside down at least 10 times. Your blood will become thicker and solidify. It shouldn’t mix with the yellow gel.

    • Your do not need to mix the red tube
03Label and post

Before you get started, take care to:

  • Follow these steps carefully
    We’ll help you make sure you’ve attached the correct labels and included everything in your return package.
  • Post your sample today
    It’s important to post your sample the same day you’ve taken it, to ensure it reaches our lab on time and your results are accurate.
Label the tube(s)
  1. Add the labels

    Peel each label from the return form and apply to each tube vertically along the length of the tube, matching the colour of the label border to the colour of the tube.

  2. If you have a colour vision deficiency

    Please ask someone to help you identify which label goes on which tube.

  3. Put each tube in its protective plastic case and close firmly
  4. Fill in the returns form

    The lab needs to know when you collected your sample. Match your details to your Thriva account information.

Pack your sample
  1. Pack your sample and form back in the box

    Using the box your kit arrived in, put the following into the section of the box labelled ‘03 SEND’:

    • Protective case(s) containing the labelled tube(s) filled right up to the required line(s)
    • Completed return form
  2. Put the box into the prepaid envelope

    This envelope has the lab’s address on it.

Seal and post
  1. Seal the prepaid envelope
  2. Post your sample
  3. Dispose of cardboard box in household recycling

    Everything else should go in normal household waste.

You did it!
Your results should be with you in as little as 48 hours, or up to 15 working days if testing Omega 3 & 6.
Watch the video guide
Important information about the finger prick lancet