Magnesium
Also known as: Serum Mg
How to prepare
You can eat and drink normally before the test.
No special preparation needed.
Tell our phlebotomist about any medicines you take. Don't stop them without asking your doctor.
Wear a loose sleeve so the sample can be taken easily from your arm.
How it works
About this test
Magnesium is a mineral needed for muscles, nerves, heart rhythm and bones.
Why is this test done?
- Find the cause of cramps or weakness
- Monitor kidney disease or diuretics
Symptoms — when should you get tested?
- Muscle cramps or twitching
- Weakness
- Irregular heartbeat
Normal range
Reference ranges differ slightly between labs, methods, age and sex. Always discuss your report with your doctor.
If your result is high
High magnesium is uncommon and usually linked to kidney disease or supplements.
Common reasons- Kidney disease
- Antacids or supplements
If your result is low
Low magnesium can cause cramps and heart rhythm problems.
Common reasons- Diarrhoea
- Alcohol
- Diuretics
- Uncontrolled diabetes
How is the test done?
- 1Book online
Choose your slot for home collection or a visit to our centre.
- 2Blood 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.
- 3Tested in our lab
Your barcoded sample is tested on automated machines with strict quality checks.
- 4Report 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.