Sodium (Na⁺)
Potassium (K⁺)
Calcium, Magnesium & Phosphate
100

This is the normal serum sodium range in mEq/L.

What is ~ 135–145 mEq/L?

100

This is the normal serum potassium range (mEq/L).

What is ~ 3.5–5.0 mEq/L?

100

Normal total serum calcium range (mg/dL).


What is ~ 8.5–10.5 mg/dL?

200

Hyponatremia can lead to this neurologic danger from brain swelling. 

What is cerebral edema / seizures / confusion?

200

Characteristic ECG change in hyperkalemia: peaked ___ waves.

What are peaked T waves?

200

Hypomagnesemia can lead to this refractory electrolyte disturbance (hint: with low Mg, this is hard to correct).

What is hypokalemia (or hypocalcemia)?

300

A hormone that promotes sodium reabsorption in the kidney.

What is aldosterone?

300

The primary mechanism by which the kidney excretes K⁺ is by this process in the distal tubule/collecting duct.

What is secretion (K⁺ secretion)?

300

This hormone or vitamin raises serum calcium (name one).

What is parathyroid hormone (PTH), or Vitamin D / calcitriol?

400

The primary cause of hypernatremia is this (too much of this or too little water).

What is water loss (dehydration) or sodium gain?

400

This diuretic class (name) can cause potassium wasting.

What are loop diuretics (e.g. furosemide) or thiazide diuretics?

400

A positive Trousseau’s sign or Chvostek’s sign suggests deficiency of this electrolyte.

What is calcium (hypocalcemia)?

500

On a lab report, this term means ‘low sodium’.

What is hyponatremia?

500

In hypokalemia, this ECG abnormality (U wave or something) is often seen.

What is a U wave (or flattened T wave, ST depression)?

500

What happens to calcium if phosphate is high?

What is hypocalcemia (low calcium)