High levels of calcium in the blood, or hypercalcemia, may lead to arrhythmias, kidney failure and, if left untreated, death. The body stores calcium in the bones, muscle cells and blood. The body eliminates most excess calcium through the urine to maintain a normal calcium level. Symptoms of hypercalcemia include nausea and vomiting, loss of appetite, excessive thirst, abdominal pain, constipation, fatigue and muscle and joint aches. Hypercalcemia may be indicative of an underlying medical condition.
Hyperparathyroidism
The parathyroid glands are tiny glands located in the neck that produce hormones to maintain the appropriate balance of calcium between the bloodstream and the tissues. Hyperparathyroidism occurs when the parathyroid glands release an excess amount of parathyroid hormone.
According to the Mayo Clinic, there are two types of hyperparathyroidism. Primary hyperthyroidism stems from an enlargement of the parathyroid glands, causing an overproduction of hormones, which results in high levels of calcium. Secondary hyperparathyroidism occurs because of another illness that has caused high levels of calcium in the body. The most common treatment for hyperparathyroidism is surgery.
Cancer
Lung and breast cancer, along with cancers of the blood such as mulitple myeloma, commonly cause an increase in calcium levels. Many cancerous tumors produce proteins that mimic parathyroid hormone, stimulating the release of calcium from the bones into the blood. Physicians refer to this as a paraneoplastic syndrome in which the body reacts to the presence of cancer or a substance the cancer produces.
A cancer that has spread to the bones may also increase the risk of hypercalcemia. Physicians will determine treatment options based on the patient's prognosis and type of cancer. In many cases, physicians prescribe medications known as biphoshonates to stop the breakdown of bone or intravenous fluids to treat dehydration.
Dehydration
Even mild dehydration may cause hypercalcemia. Dehydration occurs when a person loses more fluids than she takes in, leaving the body with too few fluids to carry out normal functions. The National Institutes of Health explains that dehydration most commonly occurs because of diarrhea, vomiting, excessive sweating and fever. Mild dehydration symptoms include dry mouth, sleepiness, thirst, decrease urine output, muscle weakness, headache and dizziness. Severe dehydration may lead to low blood pressure, rapid heart rate, lack of urination and delirium and unconsciousness. Physicians may choose to treat mild dehydration with increased fluids and electrolyte replacement beverages. Severe dehydration often requires a hospital stay and intravenous fluids.
Medications
The use of certain prescription medications may cause hypercalcemia. Lithium, which is used for the treatment of bipolar disorder, may increase the release of parathyroid hormone, causing hypercalcemia. Thiazide diuretics, which help rid the body of excess fluids, may also cause increases in calcium levels by preventing calcium excretion through urination. If a physician suspects that a patient's medications are causing the condition, the doctor may choose to replace the medication or change the dosage.
