Fasting before a blood test, explained
Which tests need it, how long, and why water is fine.
Notesp. 40
Notes from the bench.
Plain guides to tests, preparation and what happens inside a lab, written by Helix scientists. General information only, not medical advice.
What happens to your sample after it leaves your arm
The cool box, the barcode, the centrifuge and the sign-off.
Short notesp. 41
In brief
Malaria
Why a film, not just a rapid test
A stained film lets a scientist see and count parasites, which helps your doctor judge how much is there. We report what we see; treatment is for your doctor.
Genotype
Test once, keep the result
Your haemoglobin genotype does not change. Keep the report safe; many couples are asked for it before marriage.
Hydration
Drink water before a draw
Veins are easier to find when you are well hydrated, even when fasting.
Biotin
Tell us about supplements
Biotin in hair and nail products can affect some hormone tests. Pause it two days before.
The best question a patient can ask is: what do I need to do before this test?
Last word
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