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Intel Lab Diagnostics Dubai
Single Biomarker

Sodium

Blood Sodium Electrolyte

Sodium is the main electrolyte controlling fluid balance and blood pressure. Abnormal levels can cause confusion, seizures, or coma. This test is part of standard metabolic and electrolyte panels.

BLOOD24 HOURSNO FASTING
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  • Free home collection
  • Physician-reviewed report

24 Hours

Turnaround

Blood

Sample

About This Test

What the Sodium test tells you

Sodium is the dominant mineral in the fluid outside your cells, and it is what sets the pull that decides how water is distributed between the blood, the spaces between cells and the inside of cells themselves. Nerve and muscle signalling depend on the sodium gradient across cell membranes, and blood pressure and blood volume are closely tied to how much sodium the body retains. It is measured in almost every routine metabolic panel, and it is one of the most frequently abnormal results in medicine.

The single most useful thing to understand about this test is that it measures a concentration, which means it reports the balance between sodium and water rather than the amount of salt in your diet. Patients almost always assume the opposite. A low sodium usually means there is too much water relative to sodium, not that you have been eating too little salt, and a high sodium usually means water has been lost or not replaced, not that you have been eating too much. The body defends this balance through thirst, through the hormone that tells the kidney to hold on to water, and through aldosterone, which governs how much sodium the kidney keeps.

Both directions have real consequences, and because the brain is sensitive to the movement of water across its cell membranes, symptoms tend to be neurological: headache, nausea, confusion, unsteadiness, and in severe cases drowsiness or seizures. How quickly the change developed matters as much as how far it has gone, and correcting an abnormal sodium too rapidly can itself cause harm, which is why treatment is planned and supervised by a doctor rather than attempted with salt or water at home. A single abnormal value is usually confirmed and interpreted alongside your medicines, fluid intake, kidney function and how you actually feel.

Sample type
Blood
Measured in
mmol/L
Turnaround
24 Hours
Fasting
Not required
Best for
Adults & teens
Why Get Tested?

Part of routine metabolic panels. Critical for monitoring patients on diuretics, with kidney disease, heart failure, liver disease, or altered mental status.

  • Confusion or unexplained drowsiness

    The brain is the organ most sensitive to shifts in sodium, so a disturbance often shows itself as confusion or unsteadiness. Checking sodium is a routine early step in that assessment.

  • Monitoring diuretics and heart failure

    Thiazide diuretics are one of the most common causes of a low sodium, and heart, liver and kidney disease all disturb water handling. Regular testing keeps that under review.

  • Assessing dehydration

    In a hot climate, fluid losses through sweat, fever, vomiting or diarrhoea can outpace what someone drinks. Sodium shows how the water balance has actually shifted.

  • Part of every electrolyte panel

    Sodium is read together with potassium, chloride and bicarbonate to describe fluid and acid balance as a whole. The pattern across them carries more information than any single line.

When This Test Is Ordered

Reasons your doctor may request the Sodium 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.

  • Routine electrolyte testing

    • Routine inclusion in an electrolyte or general metabolic panel.

  • Confusion, drowsiness & fluid loss

    • Confusion, headache, nausea, unsteadiness or unusual drowsiness.
    • Significant vomiting, diarrhoea, fever or heat exposure with heavy sweating.

  • Medication & chronic disease

    • Ongoing treatment with diuretics, or with medicines known to affect water retention.
    • Heart failure, liver disease or kidney disease, where fluid handling is disturbed.
Preparation
The short version
No prep needed.
  • Blood
  • Free home collection
  • No fasting
  • Results in 24 Hours
  1. 1
    Book any time

    No fasting window: pick any slot that suits you, online or on WhatsApp.

  2. 2
    We come to you

    A DHA-licensed nurse collects your sample at home or in the office: free home collection.

  3. 3
    Results in 24 Hours

    A physician-reviewed, easy-to-read report lands securely by WhatsApp and email.

Prep note
Physician reviewed

No fasting is needed unless the test is grouped with glucose or lipids, in which case follow the instruction for the whole request.

Drink as you normally would: do not load up on water beforehand and do not arrive deliberately dehydrated, because either changes the very balance the test is measuring. A morning appointment is convenient but not essential.

Bring a complete medicine list, mentioning diuretics in particular, along with antidepressants, some anti-epileptic and antipsychotic medicines, and any recent change in dose, as all of these are recognised influences on sodium. Tell the clinic about recent vomiting, diarrhoea, heavy sweating or a period of unusually high fluid intake, since that context changes how the result is read.

Understanding Your Results

Sodium is a concentration, so it reports your water balance rather than how much salt you eat. A result in the Normal band, 135 to 145 mmol/L, is the usual finding. A Low result, 120 to 134 mmol/L, means relatively too much water: from thiazide diuretics, heart, liver or kidney disease, inappropriate release of the hormone that makes the kidney hold water, drinking large volumes quickly, or an underactive thyroid or adrenal insufficiency. A High result, 146 to 160 mmol/L, usually means water has been lost, through fever, heavy sweating, vomiting, diarrhoea, reduced thirst or uncontrolled diabetes. How quickly the change developed matters as much as the figure, and very high blood fats or protein can make sodium read falsely low. Correction is planned by a doctor, since changing sodium too quickly can be harmful. Your doctor reads it with your fluid status, medicines and symptoms.

SmartReport
134145
Healthy zone140mmol/LNormal
Reference ranges · mmol/L
Low
Low sodium: may relate to fluid balance. Consult your physician.
120–134
Normal
Healthy sodium level.
135–145
High
High sodium: often relates to dehydration.
146–160

Ranges are a guide: your physician interprets your result alongside your symptoms and history.

Reading a High or Low Result

  • What a higher result can point to

    • Water loss that outpaces intake, through fever, heavy sweating, vomiting or diarrhoea.
    • Reduced thirst or limited access to drinking water, which is more common in older or dependent people.
    • Diabetes insipidus, in which the kidney cannot concentrate urine and large volumes of dilute urine are passed.
    • Poorly controlled diabetes, where high blood glucose drives water out through the kidneys.
    • A large sodium load, usually from intravenous fluids given in a hospital setting.

  • What a lower result can point to

    • Thiazide diuretics, among the most frequent causes seen in everyday practice.
    • Retaining water because of heart failure, liver cirrhosis or kidney disease.
    • Inappropriate release of the hormone that makes the kidney hold water, which can follow chest infections, some cancers, brain conditions and several medicines.
    • Drinking very large volumes of water or other low-sodium fluid over a short period, including during endurance exercise.
    • An underactive thyroid or adrenal insufficiency, both of which disturb water and sodium handling.

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.

Limitations & Safety

What this test cannot tell you

  • The result describes the balance between sodium and water, so it says little about how much salt you eat and cannot be used to judge your diet.
  • Very high blood fats or protein can make sodium read falsely low on some methods, so an unexpected result is checked rather than acted on immediately.
  • A single value carries limited meaning without knowing how quickly it developed; the same figure is read differently in a sudden change than in a long-standing one.

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.
Key Points
  • 1Sodium is a concentration and mainly reflects water balance, not dietary salt intake.
  • 2A low result usually means relatively too much water; a high result usually means water has been lost.
  • 3Low sodium is the most commonly encountered electrolyte abnormality, and both directions matter.
  • 4Symptoms are mostly neurological because the brain is sensitive to water shifting across cell membranes.
  • 5Correction is planned by a doctor, since changing sodium too quickly can be harmful in itself.
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Frequently Asked Questions

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Usually not, and adding salt can be the wrong response. A low sodium most often means there is too much water relative to sodium, so the treatment is frequently about adjusting fluid intake or a medicine rather than adding salt. This is a result to discuss with your doctor before changing anything.