Hypothyroidism (underactive thyroid) is a condition in which your thyroid doesn’t make enough hormones. Though the condition usually has no symptoms in its earliest stages, untreated hypothyroidism can cause health problems, such as joint pain, obesity, infertility, and heart disease. Fortunately, hypothyroidism is easy to diagnose, and it is usually easily treated with a synthetic thyroid hormone.


The symptoms you have will depend on the severity of your hormone deficiency. However, in general, symptoms of hypothyroidism develop gradually over a number of years. Some common signs and symptoms of hyperthyroidism include weight gain, fatigue, muscle weakness, depression, dry skin, thinning hair, an increased sensitivity to the cold, and pain, swelling, or stiffness in your joints. Other signs of hypothyroidism include an elevated blood cholesterol level, impaired memory, slowed heart rate, puffy face, constipation, muscle tenderness and pain, a hoarse voice, and heavier than usual or irregular menstrual cycles.

When hypothyroidism isn’t treated, the signs and symptoms of the condition become gradually worse. Over time, you may feel depressed, become more forgetful, and your thought processes may slow down. You may also develop an enlarged thyroid (goiter). Though it is rare, severe hypothyroidism, known as myxedema, can occur, and this condition can be life-threatening. Symptoms of myxedema include low blood pressure, decreased body temperature, slowed breathing, unresponsiveness, coma, and in rare cases, death.

Causes and Risk Factors

Hypothyroidism has many potential causes, such as an autoimmune disease, removal of all or a large portion of your thyroid gland, radiation therapy to the head or neck, and treatment for hyperthyroidism. Certain medications, such as lithium, can also result in hypothyroidism. Though it is less likely, hypothyroidism can also result from a congenital disease, iodine deficiency, pituitary disorder, or pregnancy.

Anyone can develop hypothyroidism. However, certain risk factors can put you at an increased risk for developing the condition. Being a woman over the age of 60, having a family history of thyroid disease, being treated with radioactive iodine or anti-thyroid medications, being pregnant or having delivered a baby within the past six months, having an autoimmune disease, having part or all of your thyroid removed, or having received radiation to the head or neck put you at greater risk of developing hypothyroidism.

Diagnosis and Treatment

Your doctor may run a blood test to check for hypothyroidism if you are experiencing symptoms of the condition. A blood test measuring your level of thyroid stimulating hormone (TSH) will determine if you have hypothyroidism. A high level of TSH indicates that your thyroid is underactive.

In most cases, hypothyroidism is treated with the synthetic thyroid hormone, levothyroxine. Levothyroxine restores adequate hormone levels in your body, which relieves the symptoms of hypothyroidism. Treatment for hypothyroidism with levothyroxine is typically life-long. The dose of medication you need may change from time to time, so you will also need to get your TSH level checked with a blood test periodically.

Hypothyroidism is a condition in which an underactive thyroid doesn’t produce enough of the hormones your body needs. If you experience any of the symptoms of hypothyroidism, talk to your doctor about them. Your doctor can help determine if you are suffering from the condition and start you on medication, if appropriate.