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Hypercalcaemia (Secondary Care) (Guidelines)


Serum calcium levels are tightly regulated through regulatory mechanisms. Abnormalities of parathyroid function, renal calcium absorption, bone resorption, dihydroxylation of vitamin D and malignancy can result in hypo/hypercalcaemia. Calcium is bound to albumin and corrected calcium (adjusting for albumin) can be calculated using the formula: 
corrected calcium = serum calcium + 0.022 x (40 - serum albumin)
This is automatically calculated on the biochemistry report and normal serum corrected calcium levels sit between 2.2 to 2.6.
90% of hypercalcaemia is due to hyperparathyroidism or malignancy.

For the management of hypercalcaemia in Palliative Care see: Scottish Palliative Care Guidelines.



  • Gastrointestinal: Anorexia, Nausea, Constipation, Peptic Ulceration, Pancreatitis
  • Cardiac: Shortened QT, Dysrhythmias, Hypertension, Cardiomyopathy
  • Renal: Polyuria, Polydipsia, Nephrolithiasis, Nephrocalcinosis, Renal Impairment
  • Neuropsychiatric: Muscle Weakness, Mood Disturbance, Confusion, Coma

Important to ask about the duration of symptoms and symptoms suggestive of malignancy: weight loss, cough, bowel disturbance, sweats, family history, medications (including over the counter and supplements)

Initial management

  • Fluid status: urine output, HR, BP, skin temperature, CRT, thirst
  • GCS
  • Neck/respiratory/abdominal/breast/groin exam: Looking for evidence of malignancy
  • Bloods: calcium, phosphate, magnesium, PTH, U&Es, TSH, vitamin D
  • ECG +/- Cardiac monitoring
  • Stop any potentially causative medications (particularly calcium supplements and thiazide diuretics)
  • Corrected calcium, as in the table below:
Corrected calcium
<3.0If asymptomatic does not require urgent correction
3 to 3.5May be tolerated if slow rise – if symptomatic prompt treatment usually indicated
>3.5Urgent treatment; high risk of arrhythmia and coma


4 to 6L 0.9% NaCl, IV over 24 Hours

  • Tailor as appropriate for patient – reduce fluid volume in elderly, renal impairment and heart failure.
  • Loop diuretics only indicated if overloaded and will not lower calcium.
  • If severe renal impairment consider discussing with renal team re: Dialysis

After fluid resuscitation: IV bisphosphonate (NB this is an off-label indication, it is only licensed in hypercalcaemia related to malignancy)

  • Care if AKI/CKD
  • Zoledronic Acid, 4mg over 15 minutes
  • OR pamidronate, 30mg to 90mg (depending on severity) at 20mg/hour (routinely given in divided doses)
  • Calcium reaches lowest at 2 to 4 days, can stay low if vitamin D deficient (common in Scotland) or if PTH is suppressed.


  • If calcium >3.5, shortened QTC, arrhythmia, coma – escalate urgently to senior
  • Discuss with renal team early if severe AKI as may need dialysis

Further information for Health Care Professionals


Abbreviation  Meaning 
AKI  acute kidney injury 
BP  blood pressure 
CRT  cardiac resynchronisation therapy
ECG  electrocardiogram
HR  heart rate 
IV  Intravenous 
NaCI  Sodium chloride
PTH  parathyroid gland 
QTc QT corrected for heart rate
U&E  urine and electrolytes 
TSH  thyroid stimulating hormone 

Last reviewed: 31/08/2022

Next review date: 31/08/2025

Version: 1

Approved By: Approved TAMSG of the ADTC

Reviewer name(s): Euan Park, ACCS EM Trainee, Alison Heggie, Endocrinology/Acute Medicine Consultant William Rutherford, Acute Medicine/Stroke/MHDU Consultant.

Document Id: TAM538

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