Magnesium, Serum Concentration
This test measures the amount of magnesium, a mineral essential for many bodily functions, in your blood serum.
["Magnesium helps with muscle and nerve function, blood pressure, and bone health."]
Key facts at a glance
- LOINC
- 108834-3
- Short code
- Magnesium Msmt SerPl
- Synonyms
- Magnesium Msmt SerPl
- 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 check your magnesium level if you have symptoms like muscle weakness, cramps, or irregular heartbeat, or if you have conditions such as kidney disease, vomiting, or certain medications affecting magnesium levels.
What to Expect Before the Test
No special preparation is usually needed, but you may be asked to fast for a few hours before the blood draw if your provider specifies it. Wear comfortable clothing and plan to stay near the testing site for a short time.
What Happens During the Test
A healthcare professional will insert a small needle into a vein in your arm to draw blood. You may feel a slight pinch, but it usually doesn’t cause discomfort. The blood sample is then sent to a lab for analysis.
What the Results Mean
Results are compared to a standard range for healthy adults, but your specific reference range may vary based on lab standards. Low magnesium levels can cause muscle spasms or heart issues, while very high levels may lead to nausea or irregular heartbeat.
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.
Abnormal magnesium levels can indicate underlying health issues, such as electrolyte imbalances, kidney problems, or certain medical conditions. Low magnesium may contribute to muscle weakness, seizures, or heart rhythm problems, while high levels can cause symptoms like nausea, vomiting, or confusion. Regular monitoring is important for patients on long-term medications or those with chronic conditions.
Short name
Magnesium Level
Frequently asked questions
How long does it take to get my results?
What causes low magnesium levels?
What causes high magnesium levels?
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