Magnesium Test
A magnesium test measures the amount of this essential mineral in your blood. Magnesium supports muscle, nerve, and heart function, and clinicians use the marker to help evaluate magnesium status.
About this test
Magnesium is an essential mineral involved in a huge range of the body's chemical reactions. It helps muscles contract and relax, supports steady nerve signaling, takes part in producing energy, contributes to a regular heartbeat, and is a building block of bone.
The test is done with a simple blood draw at a patient service center. A phlebotomist collects a sample from a vein in the arm, and it is sent to the laboratory.
Who might consider this test?
- Look into a magnesium test when exploring symptoms that can be linked to magnesium status
- Such as muscle cramps or twitches
- A fluttering sense in the chest
Test details
| Quest code | 622 |
|---|---|
| Methodology | Spectrophotometry |
| Sample type | 1 mL serum |
| Collection | Quest patient service center |
Reference range
1.5-2.5 mg/dL
Reference ranges are general guidance. The range printed on your own laboratory report is the one that applies to your result.
Related tests and panels
A fast, on-the-go check of four essential nutrients that impact your energy,…
Measures nutrient, thyroid and stress-related markers that clinicians often…
A wide hormone and wellness panel measuring ovarian, thyroid and pituitary…
Quest resources
Additional details
What this test looks at
A magnesium test reports how much of the mineral is present in a blood sample. Magnesium is a partner in the reactions that let muscles and nerves work smoothly and that keep the heartbeat steady, so when it drifts the effects can appear in those systems. Measuring the amount in the blood gives a clinician a reference point for whether magnesium belongs in the conversation.
Because the blood holds only a small fraction of the body's total magnesium, a single blood measurement does not always reflect the amount stored inside cells and bone. A clinician keeps that limitation in mind when reading the result.
How clinicians use magnesium in context
Magnesium is often interpreted alongside related minerals such as potassium and calcium, because the body manages these together and a shift in one can echo in another. A clinician also weighs the result against medications, digestive health, and the symptoms that prompted the test.
The measurement is meant to open a conversation with a clinician rather than to answer a question by itself. From there, a clinician decides in context whether any further evaluation is worth considering.
Order online and a physician order is included — no doctor's visit and no insurance needed. Your sample is collected at a Quest Diagnostics patient service center.
Laboratory results should always be interpreted by a licensed clinician who knows your health history. This page is information about a test, not medical advice.
Frequently asked questions
What does a magnesium test measure?
It measures the amount of magnesium in the blood. Magnesium is an essential mineral involved in muscle and nerve function, energy production, a steady heartbeat, and bone structure, and the measurement reflects magnesium status.
Who commonly orders a magnesium test?
People exploring symptoms such as muscle cramps, tiredness, or a fluttering feeling in the chest often discuss it with a clinician, as do those with digestive conditions, heavy alcohol use, or certain long-term medications.
How is the sample collected?
Through a routine blood draw at a patient service center. A phlebotomist takes a small sample from a vein in the arm and sends it to the laboratory for analysis.
Does a blood test show all the body's magnesium?
No. Only a small share of the body's magnesium travels in the blood, while most is held inside cells and bone. A clinician reads the blood measurement as one useful view rather than a complete inventory.
Is magnesium tested with other minerals?
Often. Clinicians sometimes look at magnesium alongside potassium and calcium because the body manages these minerals together, and a change in one can be connected to another.
How much does the Magnesium test cost?
The cash price at Celio Health is $29. That covers the physician's order and sample collection at a Quest patient service center — no insurance is needed and there's no separate doctor's visit to pay for.