Thyroid disease is an umbrella term for conditions that affect how your thyroid functions. Hypothyroidism and hyperthyroidism are the two main types of thyroid disease. But they each have multiple possible causes. Thyroid diseases are treatable — usually with medication.
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Thyroid disease is a general term for a medical condition that keeps your thyroid from making the right amount of hormones. It can affect people of all ages.
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Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy
Your thyroid is a small, butterfly-shaped gland located at the front of your neck under your skin. It’s a part of your endocrine system and controls many of your body’s important functions by producing and releasing thyroid hormones, like thyroxine (T4) and triiodothyronine (T3).
Your thyroid’s main job is to control the speed of your metabolism (metabolic rate). This is the process of how your body transforms the food you consume into energy. All the cells in your body need energy to function. When your thyroid isn’t working properly, it can impact your entire body.
The two main types of thyroid disease are hypothyroidism (underactive thyroid) and hyperthyroidism (overactive thyroid). But they each have several conditions that can cause them.
Conditions that can cause hypothyroidism include:
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Conditions that can cause hyperthyroidism include:
Conditions that can cause both hypothyroidism and hyperthyroidism at different times include:
Thyroid disease is very common. About 20 million people in the United States have some type of thyroid condition.
There are a variety of symptoms you could experience if you have thyroid disease. Unfortunately, symptoms of a thyroid condition are often very similar to the signs of other medical conditions and stages of life. This can make it difficult to know if your symptoms are related to a thyroid issue or something else entirely.
For the most part, the symptoms of thyroid disease can be divided into two groups — those related to having too much thyroid hormone (hyperthyroidism) and those related to having too little thyroid hormone (hypothyroidism). The symptoms are often “opposites” between the two conditions. This is because hyperthyroidism speeds up your metabolism, and hypothyroidism slows down your metabolism.
Symptoms of hypothyroidism include:
Symptoms of hyperthyroidism include:
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Both conditions can cause an enlarged thyroid (goiter), but it’s more common in hyperthyroidism.
You may be at a higher risk of developing a thyroid condition if you:
Having an autoimmune disease also increases your risk, especially if you have:
Your healthcare provider will start by asking about your symptoms and medical history and doing a physical exam. During the exam, they’ll gently feel your thyroid gland to check if it’s enlarged or if there are noticeable nodules.
Your provider will need to use some thyroid tests to confirm a diagnosis. These include:
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Treatment for thyroid disease depends on the type of condition and the cause. The goal is to return your thyroid hormone levels to a healthy range.
If you have hyperthyroidism, treatment options include:
If you have hypothyroidism, the main treatment option is thyroid replacement medication. It’s a synthetic way to add thyroid hormones back into your body. One medication that providers commonly prescribe is levothyroxine.
Thyroid diseases generally aren’t preventable. This is because most cases of thyroid disease are linked to genetics and/or caused by autoimmune conditions, which you can’t prevent.
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The two conditions you may be able to prevent are thyroid problems related to iodine excess or deficiency. Talk to your healthcare provider if you’re concerned about consuming a healthy amount of iodine.
Thyroid diseases affect many parts of your body and health. If you consistently follow your treatment plan to manage the condition, it’s usually not serious.
But if thyroid disease is undiagnosed or not treated properly, it can cause complications.
Complications from untreated or undertreated hyperthyroidism include:
Complications from untreated or undertreated hypothyroidism include:
A thyroid disease is often a lifelong medical condition that you’ll need to manage consistently. This often involves daily medication. Your healthcare provider will monitor your treatments and adjust them over time.
It may take some time to find the right treatment plan for you to manage your hormone levels. But you can usually live a normal life with thyroid disease.
If you have symptoms of hypothyroidism or hyperthyroidism or notice a change in your neck’s appearance where your thyroid is, see a healthcare provider. It’s important to get a diagnosis and start treatment.
If you learn that a biological family member has a thyroid disease, be sure to update your provider so they can add it to your medical record. Thyroid diseases often run in families. It’s good to know your history in case you ever develop symptoms of thyroid disease.
A note from Cleveland Clinic
Thyroid diseases are common conditions. The good news is that medication and other treatments can help manage them well. If you have symptoms of hypothyroidism or hyperthyroidism or have known risk factors for thyroid disease, talk to your healthcare provider. They’re available to help you.
Last reviewed on 03/25/2024.
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