Thyroid Disease

Hypothyroidism is a condition that develops if the thyroid gland does not produce enough thyroid hormone. Also called underactive thyroid, hypothyroidism is more common in women, people older than 60 and those who have other conditions that affect thyroid hormone production. 

Causes of hypothyroidism include:

• Hashimoto's disease, an autoimmune disorder that causes the body to attack its own thyroid tissue
• Thyroiditis, which includes several types of disorders that can cause inflammation of the thyroid
• Congenital hypothyroidism, which means a baby is born with hypothyroidism
• Removal of part or all of the thyroid
• Radiation treatment that damages thyroid tissue
• Some medicines or chemicals that contain high amounts of iodine

Hypothyroidism symptoms may include:

• Fatigue
• Weight gain
• Inability to tolerate cold temperatures
• Pain in the joints and muscles
• Constipation
• Dry skin
• Dry, thinning hair
• Puffy skin, especially in the face 
• Decreased sweating
• Heavy or irregular menstrual periods
• Fertility problems
• Depression
• Slower heart rate

Having any of these symptoms does not mean you have hypothyroidism (underactive thyroid), but it is important to let your doctor know so that blood tests can be performed and a decision can be made about whether treatment is needed.

Hyperthyroidism is a thyroid disorder that develops when the thyroid gland produces too much hormone. Also called overactive thyroid, hyperthyroidism is more common in women, people older than 60 and those with other conditions that affect the thyroid. 

If hyperthyroidism is severe enough, it can lead to a condition called thyrotoxicosis. Without treatment, thyrotoxicosis can, rarely, become a serious health problem known as thyroid storm that causes rapid heartbeat, fever and fainting. 

Causes of hyperthyroidism include:

• Graves’ disease, which causes the body to make too much thyroid hormone
• Toxic adenomas, which are nodules that develop in the thyroid gland and produce thyroid hormones
• Subacute thyroiditis, which is inflammation of the thyroid that causes temporary hyperthyroidism 

Hyperthyroid symptoms may include:

• Weight loss
• Feeling nervous or irritable
• Mood swings
• Fatigue or muscle weakness
• Inability to tolerate heat
• Sleeping problems
• Hand tremors
• Rapid or irregular heartbeat
• Diarrhea or frequent bowel movements
• Goiter, which is the abnormal enlargement of the thyroid gland that may cause swelling in the neck

Having any of these symptoms does not mean you have hyperthyroidism (overactive thyroid), but it is important to let your doctor know so that blood tests can be performed and a decision can be made about whether treatment is needed.

Thyroiditis is inflammation of the thyroid gland. It includes several different types of endocrine disorders that cause thyroid inflammation. 

The most common types of thyroiditis are:

• Hashimoto’s thyroiditis, which is an autoimmune disorder
• Postpartum thyroiditis, which causes temporary changes in thyroid hormone levels after childbirth 
• Subacute thyroiditis, which causes thyroid pain 
• Medication-related thyroiditis, which may affect people taking interferon or other medicines  

Thyroiditis symptoms depend on how the inflammation affects the thyroid gland. If it causes a person’s thyroid hormone levels to decrease, the person will have symptoms of hypothyroidism. If thyroiditis raises thyroid hormone levels, hyperthyroidism symptoms will develop.

Thyroid cancer is cancer that begins in the thyroid gland. There are several types of thyroid cancer. About three out of four people diagnosed with thyroid cancer are women.

Symptoms of thyroid cancer include:

• A lump or swelling in the neck
• Pain in the front of the neck that may extend to the ears
• Hoarseness or a change in voice that does not get better
• Pain or difficulty swallowing
• Difficulty breathing (restricted airway)
• A constant cough not due to a cold

Many of these symptoms may be caused by other conditions that are not cancer. But let your doctor know if you’re experiencing anything unusual, so that you can identify and treat potential problems. If you have symptoms of thyroid cancer, your doctor may recommend diagnostic testing.

Treatment for hypothyroidism involves taking a synthetic thyroid hormone medicine called levothyroxine every day. Levothyroxine restores your thyroid levels to the amount your body needs and treats the symptoms of hypothyroidism. You will need to take the medicine daily for the rest of your life, but the amount you need may change over time. Most patients have their thyroid levels checked every six months or once a year to determine if their dosage needs to be adjusted.

Treatment for hyperthyroidism aims to reduce the amount of thyroid hormone in your bloodstream. Scripps thyroid doctors use several methods to do this.

• Antithyroid medicines — Prescription antithyroid drugs decrease the amount of thyroid hormone your body produces by changing how your body uses iodine. These medicines may have side effects, such as a skin rash, joint pain, fever and a lower white blood cell count.

• Radioactive iodine — Radioactive iodine is given by mouth and absorbed by the overactive thyroid cells. This damages the cells and makes them produce lower amounts of thyroid hormone. In some cases, people who receive this treatment for an overactive thyroid develop hypothyroidism (underactive thyroid) over time and need to take synthetic hormones to keep their hormones at normal levels. Radioactive iodine is not a treatment option for women who are pregnant or breastfeeding.

• Surgery — In severe cases of hyperthyroidism or cases where medication and radioactive iodine are not options, thyroidectomy surgery may be performed to remove the thyroid. Thyroidectomy patients need to take synthetic thyroid hormones for the rest of their lives.

Depending on the stage of the thyroid cancer and how far it may have spread, physicians may use several procedures to treat thyroid cancer. These include surgery, radioactive iodine therapy and hormone therapy.