Hypercalcemia is a medical condition in which there is excessive calcium in the bloodstream.[1] The normal Calcium level ranges from 8.5 to 10.2 mg/dL.[2] It is divided into three levels: Mild (10.5 to 12 mg/dL), Moderate (12 to 14 md/dL), and Critical (14 mg/dL and above).[3]

Calcium Regulation in the body

Calcium plays an essential role in the bone maintenance, muscle contraction, hormone regulation, and nervous system function. With excessive level of calcium, these functions can be interrupted. It is stored mainly at the bones, then, some can be found in the cells (muscles and blood). Normally, when calcium-rich foods are ingested in the body, the excess calcium is eliminated through urination. This causes a balance in the level of serum calcium. There are two hormones which are primarily the calcium regulators in the blood. These are:

1. Parathyroid hormone

A well-balanced calcium in the blood helps in functions such as: release of calcium from the bones going to the blood, absorption of calcium into the digestive tract, kidney excretion of less calcium and vitamin D activation.

When the body has deficient calcium level, more parathyroid hormones are released to compensate with it.
On the other hand, when the body has increased level of calcium, less parathyroid hormone is produced.

2. Calcitonin

This hormone causes the slowed release of calcium coming from the bones.

If there is an increased level of calcium in the blood, calcitonin is produced by the thyroid gland.[1]

Picture 1: The Normal Metabolism of Calcium in the Body
Source: pharmageeks.blogspot.com

Picture 2: An illustration of the Calcium Homeostasis
Source: scienceblogs.com

Picture 3: Another illustration showing how Calcium level is regulated
Source: endocrinesurgery.net.au

Hypercalcemia Causes

Abnormality in function of parathyroid gland

1. Primary hyperparathyroidism

  • This is the leading cause of hypercalcemia which occurs in 90% of patients.
  • It may be due to familial factors or may happen sporadically.
  • In this condition, PTH is released excessively by the parathyroid glands due to enlargement of one or more parts of this particular gland or an abnormal growth occurring at one of the parts of these glands.[4, 5, 6]

2. Other conditions associated with parathyroid gland abnormality

  • Use of lithium: This substance stimulates the release of more parathyroid hormones causing hypercalcemia.
  • Familial hypocalciuric hypercalcemia: This is a disorder wherein there is elevation in blood calcium due to abnormal calcium receptors. [1, 4]

Kidney Function-Associated

1. Kidney disorders

  • Acute renal failure
  • Chronic renal failure with aplastic bone disease

2. Substance intake

  • Milk-alkali syndrome
  • Intoxication in aluminium
  • Thiazide Diuretics: Intake of this medication causes elevation of calcium in the blood due to reducing calcium excreted in the urine.[1, 4, 5]


People who are suffering from different types of cancer have an increased risk for hypercalcemia. There are some malignant tumors which are involved in the production of protein that causes the release of calcium from the bones to the blood. Also, the metastasis of cancer to the bones may aggravate hypercalcemia[1]. These are some of the malignancies which are related to hypercalcemia:

1. Hematologic malignancies

  • leukemia
  • lymphoma
  • multiple myeloma

2. Solid tumor with humoral mediation

  • kidney cancer
  • lung cancer

3. Solid tumor with metastasis

  • Breast cancer [4]

Vitamin D metabolic disorders

1. Increased production of Vitamin D

  • Sarcoidosis
  • Lymphomas
  • Tuberculosis
  • Rebound hypercalcemia occurring after rhabdomyolysis
  • Idiopathic hypercalcemia in infants [4, 7]

2. Excessive dietary intake of Vitamin D

Too much vitamin D or calcium supplement intake [1]

Other Causes

  • Dehydration: This leads to decreased body fluid. Thus, the blood concentrations of calcium increase.
  • Immobility: Prolonged lying or sitting can cause hypercalcemia when the bones do not bear weight. This is due to the release of calcium from the bones to the blood.
  • Vitamin A intoxication
  • Hyperthyroidism [1, 4]

Hypercalcemia Symptoms

There are various symptoms which may appear in multiple systems. Initially, symptoms which involve the neuromuscular system are the first to manifest. However, every patient may have varying symptoms depending on the severity of the condition as well as the involved organ systems. [8]

Neuromuscular and psychiatric

1. Neurologic impairments

  • Headache: Caused by increased cerebrospinal fluid protein
  • Fatigue
  • Cognitive dysfunction: Difficulty in thinking or speaking properly
  • Impaired deep tendon reflexes
  • Hypotonic smooth and striated muscles
  • Decreased muscular strength and compromised respiratory muscles

2. Decreased Level of Consciousness

  • Disorientations
  • In severe cases, comatose may occur

3. Psychiatric

  • Depression
  • Anxiety
  • Personality changes
  • Delirium, Delusions, Hallucinations [8, 9]


1. ECG Changes

  • Prolonged PR interval
  • Shortened OT interval
  • Absent or shortened ST segments
  • Wide QRS complex
  • Atrioventricular block (may either be incomplete or complete), which may lead to complete heart block, cardiac arrest, or asystole. [8]

2. Associated conditions

  • Hypertension
  • Calcifications in the blood vessels[5]

Renal (kidney)

1. Problems in urination

  • Polyuria (Excessive urination)
  • Nocturia (Frequent urinations at night)
  • Concentrated urine [5, 8, 9]

2. Dehydration-associated

  • Polydipsia (Excessive thirst)
  • Dry mouth
  • Less or absence of sweating
  • Urine concentration[9]

3. Electrolyte imbalancesSalt and water depletion results from the reduced reabsorption of the following electrolytes:

  • Magnesium
  • Potassium
  • Sodium

4. Kidney problems

  • Decreased GFR (Glomerular Filtration Rate)
  • Kidney stones
  • Nephrogenic Diabetes Insipidus
  • Renal tubular acidosis [5, 8, 9]


1. Increase in the amount of stomach acid

  • Nausea and vomiting
  • Abdominal pain
  • Loss of appetite
  • Anorexia[5, 9]

2. Dehydration

  • Constipation[8]


1. Bones

  • Fragile bones which may result to fracture
  • Skeletal deformities
  • Pain [8]

2. Muscles

  • Muscle weakness[5]

Picture 4: Causes of Hypercalcemia
Source: blogs.nejm.org

Hypercalcemia Treatment

Medical Management

1. Mild Hypercalcemia

  • IV therapy: This is given to rehydrate the body. It is also a treatment indicated for patients who are asymptomatic and those who are more likely to respond with antineoplastic treatment.
  • Sedating medications with minimal use
  • Other treatments should focus on managing nausea and vomiting, fever, improving mobility

2. Moderate to Severe Hypercalcemia

  • Rehydration: This is a vital initial step to replace all the fluids lost, maintain the volume intravascularly, and for saline dieresis.
  • Use of hypocalcemic agents are also used to control calcium levels.
  • Drugs for preventing the bone breakdown: Calcitonin, biphophonates, gallium nitrate, plicamycin
  • Steroids and phosphates
  • Furosemide: This is given in moderate doses, usually, 20-40 mg every 12 hours. This facilitates urinary excretion of calcium.
  • Dialysis: This is indicated for patients who have kidney failure.
  • Surgery: This is especially indicated for patients who have primary hyperparathyroidism, as the underlying cause of hypercalcemia. [8, 9]

Physical Therapy Management

  • Fracture prevention
  • Range of motion exercises
  • Weight-bearing exercises for prevention of immobility and osteoporosis

Dietary Management

  • Rehydration through increased fluid intake
  • Reducing dietary consumption of foods containing calcium and vitamin D
  • Refrain from eating foods such as: low-fat dairy products, processed foods, pasteurized dairy products
  • Replacing sea salt in the diet
  • Use of probiotics¬†[8]

Psychosocial Management

1. Interventions for agitation and confusion

  • Neuroleptic medications: Haloperidol and benzodiazepine

2. Interventions for lethargy and other psychiatric disorders

  • Assessment of mental status to evaluate cognitive deficiencies
  • Antidepressants

Supportive Care

1. Safety promotion

  • This is a priority when the patient has altered level of consciousness.
  • Includes preventing self-inflicted or accidental injuries
  • Also involves fracture precautions such as gentle handling of the patient and strategies against falls

2. Supportive Care in patients with terminal stages

  • Providing comfort to the patients and their loved ones

3. Patient and Family Education

  • This includes educating them about topics such as hypercalcemia symptoms, preventions, and management. [10]

Hypercalcemia Diagnosis (Exams and Test)

Patient Assessment

1. History Taking

  • Symptoms
  • Any treatments received
  • Underlying diseases which may be related to the occurrence of hypercalcemia
  • Any previous radiographic evidences of bone diseases
  • Calcium sources

2. Clinical assessment

  • Systems review and assessment

Laboratory Work Ups

1. Renal function assessment

  • BUN (Blood Urea Nitrogen)
  • Creatinine levels

2. Immunoreactive Parathormone (iPTH)

  • To assess for iPTH concentration to rule out any hyperparathyroid disorder
  • iPTH is either reduced or undetected in cases of hypercalcemia caused by malignancy.

3. Serum electrolyte concentrations

  • To check for electrolyte balance
  • Includes magnesium, phosphate, sodium, potassium

4. Other tests:

  • Serum vitamin D concentration tests
  • Parathyroid hormone-related peptide [10]

Imaging tests

1. Plain X-raysUsed to determine presence of bone problems such as:

  • Bone cysts
  • Bony metastases
  • Pathological fractures
  • Demineralization

2. Ultrasound, CT Scan, or IV Pyelogram

  • Indicated to rule our problems in the urogenital tract
  • Can determine presence of stones or calcifications
  • Ultrasound or technetium scan may also be used for diagnosing presence of parathyroid glands adenoma or hypertrophy. [11]

Picture 5: CT Scan of the Parathyroid Glands in a patient with Hypercalcemia
Source: radiologypics.com


  1. http://www.mayoclinic.com/health/hypercalcemia/DS00976
  2. http://www.nlm.nih.gov/medlineplus/ency/article/003477.htm
  3. http://www.fpnotebook.com/renal/lab/srmclcm.htm
  4. http://en.wikipedia.org/wiki/Hypercalcaemia
  5. http://www.clevelandclinicmeded.com/medicalpubs/diseasemanagement/endocrinology/hypercalcemia/
  6. http://www.nlm.nih.gov/medlineplus/ency/article/000365.htm
  7. https://www.clinicalkey.com/topics/endocrinology/hypercalcemia.html
  8. http://www.physio-pedia.com/Hypercalcemia#Etiology.2FCauses
  9. http://www.uchospitals.edu/online-library/content=CDR62810
  10. http://www.cancer.gov/cancertopics/pdq/supportivecare/hypercalcemia/HealthProfessional/page1/AllPages
  11. http://www.patient.co.uk/doctor/Hypercalcaemia.htm

Published on by under Diseases and Conditions.
Article was last reviewed on September 7th, 2016.

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