Magnesium, Total Serum Concentration
This test measures the amount of magnesium present in your blood serum. Magnesium is an essential mineral that plays a key role in many bodily functions, including muscle and nerve function, bone health, and energy production.
["Your blood magnesium levels help ensure proper muscle and nerve function and support overall health."]
Key facts at a glance
- LOINC
- 30536-7
- Short code
- Magnesium TPN-mCnc
- Synonyms
- Magnesium TPN-mCnc
- Category
- electrolyte
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 1.7
- Ref high
- 2.2
- Critical range
- 1 N/A – 5 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 83735
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why This Test Might Be Ordered
Your healthcare provider may recommend this test if you have symptoms like muscle cramps, weakness, or irregular heartbeat. They might also order it to check for conditions like low magnesium (hypomagnesemia) or high magnesium (hypermagnesiumemia), especially if you have kidney problems, diabetes, or other health concerns. It could also be part of a routine check-up or monitoring for certain medications or conditions.
What to Expect Before the Test
You can eat and drink normally before this test. No special preparation is usually needed, but if you’re taking certain medications, discuss them with your provider. If you’re having blood drawn, make sure you’re comfortable and hydrated.
What the Test Involves
A healthcare professional will draw blood from a vein in your arm using a small needle. You may feel a slight sting, but it usually only takes a few seconds. The blood sample is then sent to a lab for analysis.
What to Expect After the Test
After the blood is drawn, you may feel a small bruise or slight discomfort at the site, which usually goes away within a day or two. Avoid vigorous activity for a short time to prevent excessive bleeding. If you experience unusual bleeding, swelling, or pain, contact your provider.
Reference range
Adult: 1.7-2.2 mg/dLN/A
No special preparation required. Stay well hydrated.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Abnormally low magnesium levels can lead to muscle spasms, cramps, weakness, irregular heartbeat, or even seizures. High magnesium levels are less common but can cause nausea, vomiting, muscle weakness, or slowed heart rate. Your provider will use the results to diagnose or monitor conditions like kidney disease, diabetes, or certain medications that affect magnesium balance.
Short name
Total Magnesium
Frequently asked questions
How long does it take to get my results?
What does a low or high magnesium level mean?
Can I eat or drink anything before this test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy