Low Potassium: what it means
A Potassium result below the normal range is considered low. Here is what a reduced Potassium can point to, and when it is worth discussing with a doctor.
Reference range: 3.5–5.0 mmol/L; critically low <3.0 or high >6.0
Understand your full resultWhat a low Potassium can mean
- Diuretics (thiazides, loop) — the most common cause.
- Gastrointestinal loss — vomiting, diarrhoea, laxative abuse.
- Renal loss — hyperaldosteronism, renal tubular acidosis.
- Magnesium deficiency — hypokalaemia is refractory to correction until magnesium is replaced.
- Insulin therapy, beta-agonists, alkalosis — shift potassium into cells.
When to discuss with a doctor
Potassium <3.0 or >6.0 mmol/L warrants urgent evaluation — these levels can trigger life-threatening arrhythmias. ECG is the next step. Mild abnormalities (3.0–3.4 or 5.1–5.9) warrant primary-care review and a repeat draw. Repeat values are essential because in-vitro haemolysis is a frequent false-positive.
Conditions this can relate to
Keep reading
One value is a snapshot. Upload the full test to see every marker explained together.
Upload your test - freeMediora.AI is informational - interpretation, not a diagnosis. A single out-of-range value is common and often benign; always discuss decisions with your doctor.