Hypothyroidism (underactive thyroid) is an endocrine disorder that occurs when a person’s body does not make enough thyroid hormone. The thyroid gland is located in the neck and produces thyroid hormone that controls how the body uses and stores energy.
One form of hypothyroidism is autoimmune thyroid disease, also called Hashimoto’s disease or Hashimoto's thyroiditis. Myxedema coma is a severe form of hypothyroidism.
There is no cure for hypothyroidism but it can be managed, and in most cases, proper treatment with thyroid replacement therapy can reverse signs and symptoms of hypothyroidism and patients can live a normal life span.
Treatment for hypothyroidism includes:
- Levothyroxine (LT4) (Synthroid, Levoxyl, Levothroid, Unithyroid) is most commonly used
- In some cases, another form of thyroid hormone, liothyronine (T3) (Cytomel, Triostat), may be given with T4
- Since T4 is converted into triiodothyronine (T3) in other organs, most studies have not shown an advantage of combining T3 and T4 over using T4 alone
- Women may need higher doses of T4 during pregnancy
What Are Symptoms of Hypothyroidism?
Symptoms of hypothyroidism may be subtle and some people may have no symptoms.
Common symptoms of hypothyroidism may include:
- Loss of energy
- Weight gain
- Decreased appetite
- Cold intolerance
- Dry skin
- Hair loss
- Joint pain
- Muscle pain
- Weakness in the extremities
- Mood swings
- Cognitive impairment
- Forgetfulness/memory impairment
- Problems concentrating
- Menstrual irregularities
- Fertility problems
- Decreased sweating
- Numbness, tingling, and nerve entrapment syndromes
- Hearing loss
- Blurred vision
- Feeling of fullness in the throat
- Nail problems such as infection, vertical white ridges on the nails, nail splitting, brittle nails, slow nail growth, and nails lifting up
Symptoms of hypothyroidism that are more specific to Hashimoto thyroiditis include:
- Painless thyroid enlargement
- A feeling of fullness in the throat
- Temporary neck pain, sore throat, or both
Symptoms of myxedema coma (severe hypothyroidism) include:
How is Hypothyroidism Diagnosed?
A doctor will take a medical history and perform a physical examination, but blood tests are used to diagnose hypothyroidism.
Blood tests used to diagnose hypothyroidism include:
- Thyroid-stimulating hormone (TSH)
- Thyroxine (T4)
- Triiodothyronine (T3)
- Thyroid antibody tests