Magnesium
Magnesium is a mineral essential for muscle and nerve function, heart rhythm, and bone health. Low levels can cause muscle cramps, fatigue, and irregular heartbeat. No fasting required.
12 hours
Turnaround
Blood
Sample
What the Magnesium test tells you
Magnesium is a mineral your body cannot manufacture and must obtain from food. Most of it is held inside bone and within cells, and only a small fraction circulates in the blood where it can be measured. Within cells it acts as a helper for a very large number of enzyme reactions, including those that release energy from food, build proteins and copy genetic material. It also has a steadying role in electrically active tissue: nerve signalling, muscle contraction and the rhythm of the heart all depend on magnesium being available.
Because the blood carries so little of the body's magnesium, the serum result is an imperfect mirror of total stores. A person can have depleted tissue magnesium while the blood level still reads within the usual range, which is one reason deficiency is often missed. Your doctor therefore interprets the number together with symptoms, medicines and the clinical situation rather than treating it as a complete account of magnesium status. Persistent muscle cramps, tremor, unusual fatigue, irritability or palpitations in someone with a reason to lose magnesium are taken seriously even when the blood figure looks unremarkable.
Magnesium is closely tied to potassium and calcium, and this connection has real practical consequences. When magnesium is depleted, the kidney handles potassium poorly and the parathyroid response to low calcium is blunted, so low potassium and low calcium can prove stubbornly resistant to replacement until the magnesium deficit itself is corrected. That is why magnesium is frequently checked alongside the other electrolytes rather than on its own, particularly in people taking diuretics, using long-term acid-suppressing medication, drinking heavily or living with poorly controlled diabetes.
Ordered when symptoms of magnesium deficiency are present (cramps, tremors, arrhythmias), in patients on diuretics, and as part of electrolyte workups.
Persistent muscle cramps, eyelid twitching and tremor are among the most common reasons magnesium is checked. These symptoms are non-specific but worth investigating when they persist.
Low potassium or calcium that will not correct with replacement often has an untreated magnesium deficit behind it. Checking magnesium can explain why treatment is not working.
Diuretics and long-term acid-suppressing medicines are recognised causes of magnesium loss. Periodic testing is a sensible part of monitoring them.
Magnesium influences the electrical stability of heart muscle, so it is often included when rhythm disturbances are being assessed. It is checked alongside potassium rather than instead of it.
Reasons your doctor may request the Magnesium test
Your doctor may order this test for any of the reasons below. Some are routine checks, others follow specific symptoms or an earlier result.
Cramps, tremor & palpitations
Muscle cramps, tremor, twitching or unusual weakness that persists without explanation.
Palpitations or an irregular heartbeat being assessed alongside other electrolytes.
Low potassium or calcium
Low potassium or low calcium that has not responded to replacement.
Medication, alcohol & absorption
Long-term use of diuretics, proton-pump inhibitors or certain other medicines that increase losses.
Regular heavy alcohol intake, or a digestive condition causing malabsorption.
No fasting window — pick any slot that suits you, online or on WhatsApp.
A DHA-licensed nurse collects your sample at home or in the office — free home collection.
A physician-reviewed, easy-to-read report lands securely by WhatsApp and email.
Magnesium supports muscle, nerve and heart function.
Ranges are a guide — your physician interprets your result alongside your symptoms and history.
What a higher result can point to
- Reduced kidney function, which lowers the body's ability to excrete magnesium.
- Magnesium-containing antacids, laxatives or supplements, especially where kidney function is impaired.
- Magnesium given as treatment in a hospital setting.
- Adrenal insufficiency, which alters how the kidney handles several minerals.
What a lower result can point to
- Poor dietary intake, or malabsorption from coeliac disease, inflammatory bowel disease or bowel surgery.
- Regular heavy alcohol intake, which increases urinary losses and often accompanies poor intake.
- Diuretics and long-term proton-pump inhibitor use.
- Poorly controlled diabetes, where high urine output carries magnesium out with it.
- Prolonged vomiting or diarrhoea, which depletes several minerals at once.
These are possibilities, not diagnoses. A single value outside the reference range is interpreted alongside your symptoms, history and other tests — your doctor decides what it means for you.
What this test cannot tell you
- The blood level reflects total body magnesium poorly, so a result within the usual range does not rule out depleted tissue stores.
- Because magnesium sits mainly inside cells, a sample damaged during collection can read falsely high.
- A supplement or antacid taken shortly before the test can lift the result temporarily and mask a genuine deficit.
Risks of the blood draw
- Mild bruising or brief soreness where the needle went in.
- Occasional lightheadedness, which settles after a few minutes of rest.
- Bleeding or infection at the site, which is rare with sterile single-use equipment.
- 1Magnesium supports nerve and muscle signalling, heart rhythm and a very wide range of enzyme reactions.
- 2Only a small part of the body's magnesium is in blood, so the test is an approximate guide to stores.
- 3Low magnesium is easy to overlook and is strongly associated with diuretics, long-term acid suppression, alcohol and poor intake.
- 4Low potassium and low calcium may resist correction until magnesium is replaced.
- 5The result is interpreted alongside symptoms, medicines and the other electrolytes.
Frequently Asked Questions
Everything you need to know about the Magnesium test. Can't find what you're looking for?
Talk to our team→Yes, and this is the main limitation of the test. Most of the body's magnesium is held in bone and inside cells, so the blood can hold a stable level while tissue stores fall. Your doctor weighs the result against your symptoms, your medicines and the rest of the electrolyte picture rather than relying on the number alone.
Magnesium is needed for the kidney to hold on to potassium properly. If magnesium is depleted, potassium keeps leaking away and replacement doses have little lasting effect, so correcting the magnesium first often makes the potassium treatment work.
Long-term use of proton-pump inhibitors is a recognised cause of low magnesium, thought to be related to reduced absorption from the gut. It usually develops over months to years rather than quickly, which is why periodic checking is sensible if you take them continuously.
That decision belongs with your doctor, because the right approach depends on why magnesium is low and on your kidney function. Supplements are handled differently when the kidneys are not clearing minerals normally, so this is not a test to act on by yourself.
Magnesium is a mineral essential for muscle and nerve function, heart rhythm, and bone health. Low levels can cause muscle cramps, fatigue, and irregular heartbeat. No fasting required.
Ordered when symptoms of magnesium deficiency are present (cramps, tremors, arrhythmias), in patients on diuretics, and as part of electrolyte workups.
No, fasting is not required for the Blood Magnesium test, so you can eat and drink normally beforehand.
The Blood Magnesium test uses a blood sample, collected quickly by our DHA-licensed phlebotomist with minimal discomfort.
Results for the Blood Magnesium test are typically ready within 12 hours. You will receive a secure digital report, and your Smart Report highlights anything outside the normal range.
The Blood Magnesium test is AED 70, which includes free home sample collection and a physician-reviewed report. You can also build a custom panel and pay only for the markers you choose.
Yes. A DHA-licensed phlebotomist can collect your sample at home or the office anywhere in Dubai at no extra cost, 7 days a week. See how it works.
It is commonly chosen by adults & teens. If you are not sure it is right for you, our care team is happy to advise.
Add the Blood Magnesium test to your cart and complete the short booking wizard, choosing home collection or a lab visit. Guest checkout lets you book without creating an account.
Yes. It is processed at our EIAC-accredited laboratory (ISO 15189:2022) under DHA license 0046381 and verified by board-certified pathologists.
Every report includes reference ranges and plain-language notes. If you have questions, our care team can arrange a clinician review — just get in touch.
Absolutely. Add it to a curated health package or bundle it with any of our 160+ biomarkers, often from a single sample in one visit.