What is Hypothyroidism
Hypothyroidism is when the thyroid gland does not make enough of certain hormones (it is underactive). The thyroid gland is a small gland located in the lower front part of the neck, just in front of the windpipe (trachea).
This gland makes hormones that help control how the body uses food for energy (metabolism) as well as how the heart and brain function. These hormones also play a role in keeping your bones strong.
When the thyroid is underactive, it produces too little of the hormones thyroxine (T4) and triiodothyronine (T3).
What are the causes?
This condition may be caused by:
- Hashimoto’s disease. This is a disease in which the body’s disease-fighting system (immune system) attacks the thyroid gland. This is the most common cause.
- Viral infections.
- Certain medicines.
- Birth defects.
- Past radiation treatments to the head or neck for cancer.
- Past treatment with radioactive iodine.
- Past exposure to radiation in the environment.
- Past surgical removal of part or all of the thyroid.
- Problems with a gland in the center of the brain (pituitary gland).
- Lack of enough iodine in the diet.
What increases the risk?
You are more likely to develop this condition if:
- You are female.
- You have a family history of thyroid conditions.
- You use a medicine called lithium.
- You take medicines that affect the immune system (immunosuppressants).
What are the signs or symptoms?
Symptoms of this condition include:
- Feeling as though you have no energy (lethargy).
- Not being able to tolerate cold.
- Weight gain that is not explained by a change in diet or exercise habits.
- Lack of appetite.
- Dry skin.
- Coarse hair.
- Menstrual irregularity.
- Slowing of thought processes.
- Sadness or depression.
How is this diagnosed?
This condition may be diagnosed based on:
- Your symptoms, your medical history, and a physical exam.
- Blood tests.
You may also have imaging tests, such as an ultrasound or MRI.
How is this treated?
This condition is treated with medicine that replaces the thyroid hormones that your body does not make. After you begin treatment, it may take several weeks for symptoms to go away.
Follow these instructions at home:
- Take over-the-counter and prescription medicines only as told by your health care provider.
- If you start taking any new medicines, tell your health care provider.
- Keep all follow-up visits as told by your health care provider.
This is important.
- As your condition improves, your dosage of thyroid hormone medicine may change.
- You will need to have blood tests regularly so that your health care provider can monitor your condition.
Contact a health care provider if:
- Your symptoms do not get better with treatment.
- You are taking thyroid replacement medicine and you:
- Sweat a lot.
- Have tremors.
- Feel anxious.
- Lose weight rapidly.
- Cannot tolerate heat.
- Have emotional swings.
- Have diarrhea.
- Feel weak.
Get help right away if you have:
- Chest pain.
- An irregular heartbeat.
- A rapid heartbeat.
- Difficulty breathing.
- Hypothyroidism is when the thyroid gland does not make enough of certain hormones (it is underactive).
- When the thyroid is underactive, it produces too little of the hormones thyroxine (T4) and triiodothyronine (T3).
- The most common cause is Hashimoto’s disease, a disease in which the body’s disease-fighting system (immune system) attacks the thyroid gland. The condition can also be caused by viral infections, medicine, pregnancy, or past radiation treatment to the head or neck.
- Symptoms may include weight gain, dry skin, constipation, feeling as though you do not have energy, and not being able to tolerate cold.
- This condition is treated with medicine to replace the thyroid hormones that your body does not make.