• PTH from the parathyroid glands.
• Calcitonin from the thyroid gland.
• “PTH pulls calcium out of the bone” and is stimulated by hypocalcemia.
• “Calcitonin keeps calcium in the bone” and is stimulated by hypercalcemia.
• Hyperparathyroidism results in hypercalcemia and a risk for renal calculi.
• Hypoparathyroidism results in hypocalcemia and a risk for osteoporosis.

• “Ca++, and Mg+ are parallel to each other.”
• “HPO4 is the opposite of Ca++ and Mg+ in the absence of some disorders.”
• A diet high is phosphorus leads to ↑ HPO4, ↓ Ca++, ↓ Mg+
• Hyperparathyroidism leads to ↑ Ca++, ↑ Mg+, ↓ HPO4.
• In renal failure, the relationship does not exist.
    • Excretion of magnesium and phosphorus are impaired.
    • Calcium reabsorption is impaired.
    • Lab values ↑ Mg+, ↑ HPO4, ↓ Ca++.

The clinical manifestations of calcium, magnesium, and phosphorous are similar.

• Muscle twitching and seizure activity with ↓ Ca++, ↓ Mg+, and ↑ HPO4.
• Everything slows down (“nothing”) with ↑ Ca++, ↑ Mg+, and ↓ HPO4.
• Memory Hint: “Twitch, twitch, seize, seize” and then “Nothing”.

Chvostek’s and Trousseau’s are clinical assessments for muscle twitching.

Hypocalcemia
• Initiate seizure precautions.
• Increase oral intake with milk, cheese, yogurt, and greens such as spinach.
• Calcium supplements orally.
• Vitamin D to increase calcium absorption.
• Calcium supplements intravenously with ECG monitoring for signs of hypercalcemia and monitoring for infiltration since it is a vesicant solution.

Hypomagnesemia
• Initiate seizure precautions.
• Increase oral intake with meats, canned white fish tuna, oats, potatoes, milk, raisins, leafy vegetables, and peanut butter.
• Magnesium supplements orally.
• Magnesium sulfate intravenously while monitoring deep tendon reflexes suggesting an increased level, and monitoring for infiltration since it is a vesicant solution.
• Calcium chloride or calcium gluconate IV as the antidote for overdose or to reverse cardiac effects.

Hypercalcemia and Hypermagnesemia
• Monitor for flank and abdominal pain indicative of renal calculi.
• Push fluids to around 3,000 mL to prevent renal calculi.
• Diuretics to increase renal excretion.
• Calcitonin (Miacalcin) or bisphosphonates to keep calcium in the bone.
• Dialysis for severe calcium elevation of ≥ 14 mg/dL and a comatose state.

Memory Hints in Calcium and Magnesium
• PTH pulls and calcitonin keeps.
• Ca++, and Mg+ are parallel to each other.
• HPO4 is the opposite of Ca++ and Mg+ in the absence of some disorders.
• “Twitch, twitch, seize, seize” and then “Nothing”.
• Least invasive before more invasive.

In preparing for the NCLEX exam, knowledge about calcium and magnesium electrolyte imbalances is important. Using some of these “Memory Hints” will help to correlate some the interrelationships that exist and clinical manifestations.

In looking at the clinical manifestations of the imbalances, do a compare-and-contrast, especially for test taking purposes. Think through how the causes effect the electrolytes, such as with the hormones calcitonin and PTH. And with treatment, safety first such as seizure precautions. Then treatment using least invasive (and safest) first such as dietary replacement. Then oral and intravenous.