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

The low production of PTH in hypoparathyroidism leads to abnormally low calcium levels in your blood 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.

Signs and symptoms of hypoparathyroidism can include:

• Tingling or burning in your fingertips, toes and lips
• Muscle aches or cramps in your legs, feet, stomach or face
• Twitching or spasms of your muscles, particularly around your mouth, but also in your hands, arms and throat
• Fatigue or weakness
• Painful menstrual periods
• 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. These can both be complications of hypoparathyroidism.

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

Factors that can cause hypoparathyroidism include:

• Neck surgery. This most common cause of hypoparathyroidism develops after accidental damage to or removal of the parathyroid glands during surgery. Neck surgery may be done to treat conditions of the thyroid gland, or to treat throat or neck cancer.
• Autoimmune disease. In some cases, your immune system attacks parathyroid tissues as if they were foreign bodies. In the process, the parathyroid glands stop producing 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.
• Low levels of magnesium in your blood. Low magnesium levels can affect the function of your parathyroid glands. Normal magnesium levels are required for normal production of parathyroid hormone.
• Extensive cancer radiation treatment of your face or neck. Radiation can result in destruction of your parathyroid glands. In rare cases, radioactive iodine treatment for hyperthyroidism may lead to hypoparathyroidism.

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 a decrease in the hormones your adrenal glands produce

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:

• Cramplike spasms of your hands and fingers that can be prolonged and painful, or muscle pain 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.
• Tingling or burning sensations, or a pins and needles feeling, in your lips, tongue, fingers and toes.
• Seizures.
• Malformed teeth, affecting dental enamel and roots, in cases when hypoparathyroidism occurs at an early age when teeth are developing.
• Problems with 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
• Slow mental development in children
• Calcium deposits in the brain, which can cause balance problems and seizures
• Clouded vision due to cataracts

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. Your doctor may choose to test your calcium, parathyroid hormone and vitamin D levels and have you begin supplementation if needed before surgery.

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.

A doctor who suspects hypoparathyroidism will take a medical history and conduct a physical exam.

Blood tests

These findings on blood tests might indicate hypoparathyroidism:

• A low blood-calcium level
• A low parathyroid hormone level
• A high blood-phosphorus level
• A low blood-magnesium level

Your doctor might also order a urine test to determine whether your body is excreting too much calcium.

The goal of treatment is to relieve symptoms and to normalize levels of calcium and phosphorus in your body. A treatment regimen usually includes:

• Oral calcium carbonate tablets. Oral calcium supplements can increase calcium levels in your blood. However, at high doses, calcium supplements can cause gastrointestinal side effects, such as constipation, in some people.
• Vitamin D. High doses of vitamin D, generally in the form of calcitriol, can help your body absorb calcium and eliminate phosphorus.
• Magnesium. If your magnesium level is low and you're experiencing symptoms of hypoparathyroidism, your doctor may recommend that you take a magnesium supplement.
• Thiazide diuretics. If your calcium levels remain low even with treatment, thiazide diuretics can help decrease the amount of calcium lost through your urine. However, some people with hypoparathyroidism, including people who inherited the condition, shouldn't take thiazide diuretics.
• Parathyroid hormone (Natpara). The U.S. Food and Drug Administration has approved this once-daily injection for treatment of low blood calcium due to hypoparathyroidism. Because of the potential risk of bone cancer (osteosarcoma), at least in animal studies, this drug is available only through a restricted program to people whose calcium levels can't be controlled with calcium and vitamin D supplements and who understand the risks.

Diet

Your doctor might recommend that you consult a dietitian, who is likely to advise a diet that's:

• Rich in calcium. This includes dairy products, green leafy vegetables, broccoli and foods with added calcium, such as some orange juice and breakfast cereals.
• Low in phosphorus. This means avoiding carbonated soft drinks, which contain phosphorus in the form of phosphoric acid, and limiting meats, hard cheeses and whole grains.

Intravenous infusion

If you need immediate symptom relief, your doctor might recommend hospitalization so that you can receive calcium by intravenous (IV) infusion, as well as oral calcium tablets. After hospital discharge, you'll continue to take calcium and vitamin D orally.

Monitoring

Your doctor will regularly check your blood to monitor levels of calcium and phosphorus. Initially, these tests will probably be weekly to monthly. Eventually, you'll need blood tests just twice a year.

Because hypoparathyroidism is usually a long-lasting disorder, treatment generally is lifelong, as are regular blood tests to determine whether calcium is at normal levels. Your doctor will adjust your dose of supplemental calcium if your blood-calcium levels rise or fall.

You'll likely start by seeing your primary care doctor. You might then be referred to a doctor trained in treating hormone disorders (endocrinologist).

Here's some information to help you get ready for your appointment.

What you can do

When you make the appointment, ask if there's anything you need to do in advance, such as fasting for a specific test. Make a list of:

• Your symptoms, including those that seem unrelated to the reason for which you scheduled the appointment, and when they began
• Key personal information, including major stresses or recent life changes and your and your family's medical history
• All medications, vitamins and other supplements you take, including doses
• Questions to ask your doctor

Take a family member or friend with you, if possible, to help you remember the information you're given.

For hypoparathyroidism, questions to ask your doctor include:

• What is likely causing my symptoms?
• What are other possible causes?
• What tests do I need?
• Is my condition likely temporary or chronic?
• What treatments are available, and which do you recommend?
• What are the alternatives to the primary approach you're suggesting?
• How can I best manage this condition with my other health conditions?
• Do I need to change my diet?
• Are there brochures or other printed material I can take? What websites do you recommend?

Don't hesitate to ask other questions.

What to expect from your doctor

Your doctor is likely to ask you questions, including:

• Have you recently had surgery involving your neck?
• Have you received radiation therapy to your head or neck or for treatment of thyroid problems?
• Has anyone in your family had similar symptoms?
• Have your symptoms been continuous or occasional?
• How severe are your symptoms?
• What, if anything, seems to improve your symptoms?
• What, if anything, appears to worsen your symptoms?