Electrolyte Fast Facts Notes

Electrolyte Fast Facts

Sodium: 135 – 145 MEQ/L

  • Think: BRAIN
    • Water follows sodium, which regulates fluid volume.
  • Enters the Body:
    • Via diet: salty and processed foods.
  • Lost Via:
    • GI tract, kidneys.
  • Conditions Related to Sodium Levels:
    • Hyponatremia: Confusion, hypotension, muscle cramps & weakness.
    • Severe Hyponatremia (
    • Hypernatremia: Restlessness, altered mental status (AMS), hallucinations, potential for permanent brain damage.

Potassium: 3.5 – 5 MEQ/L

  • Think: HEART
    • Electrical impulses in nerve, heart, skeletal tissue; helps in acid-base regulation.
  • Enters the Body:
    • Via diet: bananas, citrus, potatoes, avocados, whole grains.
  • Lost Via:
    • Kidneys (e.g., loop diuretics), diarrhea, emesis.
  • Conditions Related to Potassium Levels:
    • Hypokalemia: Cramps, fatigue, ventricular tachycardia (can lead to death).
    • Hyperkalemia: Weakness, heart block, ventricular tachycardia (can lead to death).
    • Caution: Lethal injections involve potassium; NEVER administer via IV push.

Magnesium: 1.3 – 2.3 MEQ/L

  • Think: HEART
    • Important for neuromuscular function and cardiac relaxation (vasodilation); helps regulate acid-base.
  • Enters the Body:
    • Via diet: green leafy vegetables, nuts, seafood, peas, beans.
  • Lost Via:
    • Kidneys (e.g., loop diuretics).
  • Conditions Related to Magnesium Levels:
    • Hypomagnesemia: Muscle weakness (early), tetany (late), can lead to Torsades de Pointes (sudden cardiac death).
    • Hypermagnesemia: Nausea, loss of deep tendon reflexes, respiratory depression.

Calcium: 8.6 – 10.2 MEQ/L

  • Think: BONES AND TEETH
    • Body uses bones as a reservoir to maintain calcium levels; regulates muscle & cardiac contraction, major component of bones & teeth.
  • Enters the Body:
    • Via diet: milk, green leafy vegetables, whole grains.
    • Needs vitamin D for absorption.
  • Lost Via:
    • GI tract, inverse relationship with phosphorus (high phosphate = low calcium).
  • Conditions Related to Calcium Levels:
    • Hypocalcemia: Paresthesia (tingling in fingers and mouth), muscle cramps.
    • Hypercalcemia: Nausea, constipation; severe hypercalcemia can cause cardiac arrest.
    • Cancers can cause hypercalcemia by secreting parathyroid hormone (PTH), which pulls calcium from bones - indicates poor prognosis.

Phosphate: 2.5 – 4.5 MEQ/L

  • Inverse Relationship with Calcium:
    • If phosphate levels are high, calcium levels will be low (will pull calcium from bones).
  • Functions:
    • Bone and teeth formation, red blood cell (RBC) function, energy storage.
  • Enters the Body:
    • Via diet: animal products, cereals, dark soda.
  • Lost Via:
    • Kidneys.
  • Conditions Related to Phosphate Levels:
    • Hypophosphatemia: Irritability, fatigue, weakness.
    • Hyperphosphatemia: Muscle cramps and weakness.

Chloride: 97 – 107 MEQ/L

  • Besties with Sodium:
    • Works closely with sodium to maintain osmotic pressure.
  • Enters the Body:
    • Via diet: commonly through salt.
  • Lost Via:
    • Kidneys with sodium loss.
  • Conditions Related to Chloride Levels:
    • Hypochloremia: Hyperactive deep tendon reflexes, weakness.
    • Hyperchloremia: Tachypnea, weakness, lethargy.