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This test checks the level of magnesium in your blood. Magnesium is an important electrolyte. It's needed for proper muscle, nerve, and enzyme function. It also helps the body make and use energy.
Most of the magnesium in the body is found in the bones and inside the cells. Only a tiny amount of magnesium is normally found in the blood.
This test is used to find a cause for nerve and muscle problems. These include muscle twitches and weakness and irritability. It can see if people with heart problems need extra magnesium. Other uses are to check levels when magnesium is being given for medical treatment and check how well your kidneys are working.
Don't take medicines containing magnesium for at least 3 days before this test. This includes:
A health professional uses a needle to take a blood sample, usually from the arm.
The test will take a few minutes.
Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor or nurse advice line (811 in most provinces and territories) if you are having problems. It's also a good idea to keep a list of the medicines you take. Ask your doctor when you can expect to have your test results.
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Current as of: September 8, 2022
Author: Healthwise Staff
Medical Review:Kathleen Romito MD - Family Medicine & Adam Husney MD - Family Medicine & Martin J. Gabica MD - Family Medicine
Care instructions adapted under license by your healthcare professional. If you have questions about a medical condition or this instruction, always ask your healthcare professional. Healthwise, Incorporated disclaims any warranty or liability for your use of this information.
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