Blood test

Low potassium level in the blood

Blood test
Low potassium level in the blood
Last update: 18/03/2020

What is low potassium level in blood called?

  • Hypokalemia

What is the normal level of potassium in the blood?

If you need to know which are the potassium reference ranges or you require more information about the role of potassium in the blood, you can visit normal potassium level in the blood

What does a low blood potassium level mean?

Hypokalemia (low potassium) is usually due to:

  • Metabolic disorders (metabolic alkalosis)
  • Increased potassium excretion (hyperaldosteronism, renal tubular acidosis, diarrhea)
  • A low potassium diet

Potassium blood values are usually given in mEq/L but sometimes you can see these values in mmol/l following the International System of Units (SI). Numerical values are similar in mmol/L or in mEq/L

Hypokalemia or low potassium blood levels mean:

  • Mild hypokalemia (3.0 - 3.5 mEq/L in adults):

    Your potassium level is a bit low. It may be due to low potassium diet so you can try to increase food high in potassium in your diet.

    If you suffer from arrhythmias, muscle weakness or fatigue it is recommended a visit to your doctor.

  • Marked hypokalemia (2.5 - 3 mEq/L in adults):

    It is necessary to raise these levels to prevent from muscle atrophy.

    Marked hypokalemia is related to paralysis or breathing problems.

    You must visit your doctor because sometimes you may require hospitalization to follow the appropriate treatment.

  • Severe hypokalemia (< 2.5 mEq/L in adults):

    Severe hypokalemia can lead to life-threatening cardiac conduction disturbances (arrhythmias) and neuromuscular dysfunction like sinus bradycardia, ventricular tachycardia or fibrillation.

    You need to look for urgent medical attention. Parenteral potassium replacement 8 Intravenous potassium) under medical supervision is the best practice for patients with severe hypokalemia.

Which factors can reduce potassium blood levels?

There are some circumstances or drugs than can reduce your potassium levels in the blood:

  • Diarrhea
  • Unhealthy diet
  • Vomiting
  • Drugs

Which diseases can reduce your potassium blood levels?

Lower than normal levels of potassium in the blood can be due to:

What can I do to increase potassium blood levels?

If your potassium blood level is a bit low, the following tips can help you:

  • Increase potassium intake. Examples of potassium rich foods are:
    • Vegetables Asparagus, potatoes, tomatoes, carrots, squash, spinach
    • Fruits: Bananas, avocados, oranges, kiwis and figs
    • Fish: Salmon.
    • Whole grains and milk.
  • Potassium supplements: Talk to your doctor to know if they are appropriate for you.

Where can I find more information about potassium in the blood?

You can visit our pages about:

Which values are considered a low potassium level in the blood?

The following values are considered to be below the normal range:

IMPORTANT: These levels are expressed in mEq/L (mmol/L). They are an example for a healthy man of about 45 years of age with no known disease, not taking any medication and with an appropriate intake of potassium in diet. The ranges can be different depending on the laboratory or on your personal circumstances.

Mild hypokalemia
3.4 mEq/L3.3 mEq/L3.2 mEq/L3.1 mEq/L3 mEq/L   
Marked hypokalemia
2.9 mEq/L2.8 mEq/L2.7 mEq/L2.6 mEq/L2.5 mEq/L   
Severe hypokalemia
2.4 mEq/L2.3 mEq/L2.2 mEq/L2.1 mEq/L2 mEq/L1.9 mEq/L1.8 mEq/L1.7 mEq/L
1.6 mEq/L1.5 mEq/L1.4 mEq/L1.3 mEq/L1.2 mEq/L1.1 mEq/L1 mEq/L 
Medically reviewed by Javier Muga Bustamante Ph.D. on 18/03/2020


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