Hypokalemia: Symptoms, Causes, Treatment, and Prevention

Clinical Manifestations

• Muscle weakness, fatigue, cramps (impaired excitability)
• Paralysis (severe, <2.5 mEq/L)
• Cardiac arrhythmias: U waves, ST depression, VT/VF risk
• Hypertension: Sodium retention, vascular sensitivity
• Renal: Polyuria, nephrogenic diabetes insipidus, stone risk
• GI: Ileus, nausea, vomiting, constipation
• Neuropsychiatric: Confusion, lethargy, psychosis (severe)

Common Causes

• Diuretic therapy (loop, thiazide)
• GI losses (vomiting, diarrhea, laxative abuse)
• Hyperaldosteronism, Cushing’s, licorice excess
• Renal tubular disorders (Bartter, Gitelman)
• Insulin/beta-agonist shift (transient)
• Inadequate intake (rare alone)

Treatment

• Oral KCl: 20–40 mEq 2–4×/day for mild-moderate; monitor serum K⁺.
• IV KCl: For severe (<2.5 mEq/L), symptomatic, or unable to take oral. Max 10 mEq/h peripheral, 20 mEq/h central with cardiac monitoring.
• Potassium-sparing diuretics (spironolactone, amiloride) if ongoing losses.
• Address underlying cause.

Dietary Sources (≥300 mg/serving)

• Bananas, oranges, cantaloupe, potatoes, spinach, beans, nuts, seeds, dairy, salmon.

Prevention

Balanced diet rich in fruits/vegetables; monitor electrolytes with diuretics; avoid excessive licorice; treat GI losses promptly.