Overview

Hypoparathyroidism is an uncommon condition in which your body secretes abnormally low levels of parathyroid hormone (PTH). PTH is key to regulating and maintaining a balance of your body's levels of two minerals — calcium and phosphorus.

The low production of PTH in hypoparathyroidism leads to abnormally low calcium levels in your blood and bones and to an increase of phosphorus in your blood.

Supplements to normalize your calcium and phosphorus levels treat the condition. Depending on the cause of your hypoparathyroidism, you'll likely need to take supplements for life.

Symptoms

Signs and symptoms of hypoparathyroidism can include:

  • Tingling or burning (paresthesia) in your fingertips, toes and lips
  • Muscle aches or cramps in your legs, feet, abdomen or face
  • Twitching or spasms of your muscles, particularly around your mouth, but also in your hands, arms and throat
  • Fatigue or weakness
  • Painful menstruation
  • Patchy hair loss
  • Dry, coarse skin
  • Brittle nails
  • Depression or anxiety

When to see a doctor

If you have signs or symptoms associated with hypoparathyroidism, see your doctor for an evaluation. Contact your doctor immediately if you have a seizure or have difficulty breathing, both of which can be complications of hypoparathyroidism.

Causes

Hypoparathyroidism occurs when your parathyroid glands don't secrete enough parathyroid hormone. You have four small parathyroid glands situated in your neck, behind your thyroid gland.

Factors that can cause hypoparathyroidism include:

  • Post-surgical hypoparathyroidism. This most common cause of hypoparathyroidism develops after accidental damage to or removal of the parathyroid glands during surgery. This surgery might be a treatment for diseases of the thyroid gland, or for throat or neck cancer.
  • Autoimmune disease. Your immune system creates antibodies against the parathyroid tissues, trying to reject them as if they were foreign bodies. In the process, the parathyroid glands stop manufacturing their hormone.
  • Hereditary hypoparathyroidism. In this form, either you're born without parathyroid glands or they don't work properly. Some types of hereditary hypoparathyroidism are associated with deficiencies of other hormone-producing glands.
  • Extensive cancer radiation treatment of your face or neck. Radiation can result in destruction of your parathyroid glands, as can radioactive iodine treatment for hyperthyroidism, occasionally.
  • Low levels of magnesium in your blood, which can affect the function of your parathyroid glands. Normal magnesium levels are required for optimum secretion of parathyroid hormone.

Risk factors

Factors that can increase your risk of developing hypoparathyroidism include:

  • Recent neck surgery, particularly if the thyroid was involved
  • A family history of hypoparathyroidism
  • Having certain autoimmune or endocrine conditions, such as Addison's disease — which causes your adrenal glands to produce too little of its hormones

Complications

Hypoparathyroidism can result in various complications.

Reversible complications

The following are due to low calcium levels, most of which are likely to improve with treatment:

  • Tetany. These cramplike spasms of your hands and fingers can be prolonged and painful. Tetany might also include muscle discomfort and twitches or spasms of the muscles of your face, throat or arms. When these spasms occur in your throat, they can interfere with breathing, creating a possible emergency.
  • Paresthesias. These are characterized by odd, tingling sensations or pins and needles feelings in your lips, tongue, fingers and toes.
  • Loss of consciousness with convulsions (grand mal seizures).
  • Malformed teeth, affecting dental enamel and roots.
  • Impaired kidney function.
  • Heart arrhythmias and fainting, even heart failure.

Irreversible complications

Accurate diagnosis and treatment might prevent these complications associated with hypoparathyroidism. But once they occur, calcium and vitamin D won't improve them:

  • Stunted growth (short stature)
  • Slow mental development in children
  • Calcium deposits in the brain, which can cause balance problems and seizures
  • Cataracts

Prevention

There are no specific actions to prevent hypoparathyroidism. However, if you're scheduled to have thyroid or neck surgery, talk to your surgeon about the risk of damage to your parathyroid glands during the procedure.

If you've had surgery involving your thyroid or neck, watch for signs and symptoms that could indicate hypoparathyroidism, such as a tingling or burning sensation in your fingers, toes or lips, or muscle twitching or cramping. If they occur, your doctor might recommend prompt treatment with calcium and vitamin D to minimize the effects of the disorder.