Hyperthyroidism, also called an overactive thyroid, is a condition in which the thyroid gland produces too much thyroid hormone. The thyroid is a small, butterfly-shaped gland located in the front of your neck that helps regulate your body’s metabolism, heart rate, body temperature, digestion, and energy levels.
When the thyroid produces too much hormone, many body functions speed up. This can cause symptoms such as weight loss, a rapid heartbeat, anxiety, tremors, and heat intolerance. Hyperthyroidism is a treatable condition, and many people successfully manage it with medications, radioactive iodine therapy, or surgery.
Hyperthyroidism – NIH MedlinePlus
https://medlineplus.gov/hyperthyroidism.html
Provides easy-to-understand information about hyperthyroidism, including symptoms, diagnosis, treatment, and long-term management.
Hyperthyroidism (Overactive Thyroid) – American Thyroid Association
https://www.thyroid.org/hyperthyroidism/
Explains what hyperthyroidism is, why it develops, treatment options, and frequently asked questions.
Hyperthyroidism affects millions of people worldwide and is more common in women than men. It can occur at any age but is most often diagnosed between the ages of 20 and 50. The most common cause is Graves’ disease, an autoimmune disorder.
American Thyroid Association – Hyperthyroidism
https://www.thyroid.org/hyperthyroidism/
Provides information about who is most likely to develop hyperthyroidism and common risk factors.
Symptoms may develop gradually or appear suddenly, depending on the cause.
Common symptoms may include:
Some people with Graves’ disease may also develop:
Your healthcare provider will review your symptoms, perform a physical examination, and order blood tests to evaluate your thyroid hormone levels. Depending on the suspected cause, imaging studies or additional testing may also be recommended.
Hyperthyroidism – NIH MedlinePlus
https://medlineplus.gov/hyperthyroidism.html
Explains how hyperthyroidism is diagnosed and what testing may be recommended.
Several conditions can cause the thyroid gland to produce too much thyroid hormone.
Common causes include:
Hyperthyroidism – NIH MedlinePlus
https://medlineplus.gov/hyperthyroidism.html
Learn about the common causes of hyperthyroidism and risk factors.
Several factors can worsen symptoms or interfere with treatment.
Common factors include:
American Thyroid Association
https://www.thyroid.org/
Provides practical guidance on managing hyperthyroidism and avoiding factors that may worsen symptoms.
Not all cases of hyperthyroidism can be prevented, especially autoimmune conditions such as Graves’ disease. However, early diagnosis and treatment can reduce the risk of serious complications.
Helpful prevention tips include:
American Thyroid Association
https://www.thyroid.org/
Provides practical information about thyroid health, medication management, and long-term care.
The following video content is provided to help you better understand this condition. These resources are intended for educational purposes and should not replace personalized medical advice from your healthcare provider.
Laboratory testing is the primary way hyperthyroidism is diagnosed and monitored.
Common laboratory tests may include:
TSH Test – NIH MedlinePlus
https://medlineplus.gov/lab-tests/tsh-thyroid-stimulating-hormone-test/
Explains how TSH testing is used to diagnose and monitor hyperthyroidism.
Additional testing helps determine the cause of hyperthyroidism and evaluate thyroid structure.
Common diagnostic tests include:
American Thyroid Association – Thyroid Function Tests
https://www.thyroid.org/thyroid-function-tests/
Provides information about thyroid blood tests, imaging studies, and diagnostic testing.
Treatment depends on the cause of hyperthyroidism, your age, overall health, and the severity of your symptoms.
Treatment options may include:
Hyperthyroidism – American Thyroid Association
https://www.thyroid.org/hyperthyroidism/
Provides information about treatment options and long-term management of hyperthyroidism.
Healthy lifestyle habits can support your treatment plan and improve your overall well-being.
Helpful lifestyle changes include:
American Thyroid Association
https://www.thyroid.org/
Provides practical guidance for living well with hyperthyroidism.
Several medications are available to treat hyperthyroidism and control symptoms.
Common medications include:
Methimazole – NIH MedlinePlus
https://medlineplus.gov/druginfo/meds/a682464.html
Provides information about methimazole, proper use, side effects, and monitoring.
Propylthiouracil – NIH MedlinePlus
https://medlineplus.gov/druginfo/meds/a682465.html
Explains how propylthiouracil works, common side effects, and important safety information.
Some people with hyperthyroidism may require procedures to diagnose, monitor, or treat their condition. The type of procedure depends on the cause of the overactive thyroid, the severity of symptoms, and how well medications control the condition.
Common procedures may include:
American Thyroid Association
https://www.thyroid.org/
Learn about radioactive iodine therapy, thyroid surgery, and other treatment options for hyperthyroidism.
Most people with hyperthyroidism respond well to treatment and are able to live healthy, active lives. Some individuals achieve long-term remission with medication, while others require radioactive iodine therapy or surgery.
After treatment with radioactive iodine or thyroid surgery, many people develop hypothyroidism and will need lifelong thyroid hormone replacement medication. Regular blood tests help ensure thyroid hormone levels remain in a healthy range.
Daily self-care is an important part of managing hyperthyroidism and preventing complications.
Helpful tips include:
American Thyroid Association
https://www.thyroid.org/
Provides practical guidance for living well with hyperthyroidism and understanding your treatment options.
Graves’ disease is an autoimmune condition and the most common cause of hyperthyroidism. It causes the immune system to stimulate the thyroid gland to produce too much thyroid hormone.
Some people only need anti-thyroid medications for a limited period, while others require lifelong thyroid hormone replacement after radioactive iodine therapy or surgery.
Yes. Untreated hyperthyroidism can cause rapid heart rate, irregular heart rhythms (such as atrial fibrillation), high blood pressure, and other heart-related complications.
Yes. Some people with Graves’ disease develop Graves’ eye disease, which may cause eye irritation, dryness, bulging eyes, double vision, or vision problems.
Your healthcare provider will determine how often your thyroid function should be monitored. Blood tests are commonly repeated after starting or adjusting treatment and then periodically once your thyroid levels are stable.
Consider asking your healthcare provider:
When should I schedule my next follow-up appointment?
Many people with hyperthyroidism receive care from their primary care provider. Depending on the cause and severity of your condition, your provider may recommend seeing a specialist.
You may be referred to:
American Thyroid Association
https://www.thyroid.org/
Provides patient education about thyroid disorders, specialty care, and treatment options.
Some causes of hyperthyroidism can be permanently treated with radioactive iodine therapy or thyroid surgery. Others may go into remission after treatment with anti-thyroid medications.
Many people who receive definitive treatment develop hypothyroidism and require lifelong thyroid hormone replacement. With appropriate treatment and monitoring, most people live healthy, active lives.
Call 911 or seek emergency medical care immediately if you experience:
These symptoms may be signs of thyroid storm, a rare but life-threatening complication of severe hyperthyroidism.
Seek prompt medical evaluation if you notice:
Hyperthyroidism – NIH MedlinePlus
https://medlineplus.gov/hyperthyroidism.html
Learn about hyperthyroidism, potential complications, and when emergency medical care is needed.
CALL 911
APNS does not provide emergency medical services. If you believe you are experiencing a medical emergency, including (but not limited to) chest pain, difficulty breathing, stroke symptoms, severe allergic reactions, anaphylaxis, uncontrolled bleeding, seizures, loss of consciousness, or any other potentially life-threatening condition, you are instructed to call 911 immediately or go immediately to the nearest emergency department.
https://medlineplus.gov/hyperthyroidism.html
Easy-to-understand information about hyperthyroidism, including symptoms, diagnosis, treatment, and long-term management.
American Thyroid Association – Hyperthyroidism
https://www.thyroid.org/hyperthyroidism/
Comprehensive patient education about Graves’ disease, hyperthyroidism, medications, radioactive iodine therapy, surgery, and follow-up care.
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
https://www.niddk.nih.gov/health-information/endocrine-diseases
Reliable information about thyroid disease and other endocrine disorders.
Hormone Health Network
https://www.hormone.org/
Evidence-based patient education about thyroid disorders, hormone health, and endocrine conditions.
This guide is intended for educational purposes only and should not replace medical advice, diagnosis, or treatment from your healthcare provider. Always follow the recommendations of your healthcare team regarding your individual health needs. Contact your healthcare provider if your symptoms worsen, new symptoms develop, or your treatment is no longer controlling your hyperthyroidism. Call 911 immediately if you experience chest pain, difficulty breathing, severe confusion, loss of consciousness, or symptoms of thyroid storm or another medical emergency.
At APNS, our providers take the time to understand your condition and your goals. We offer comprehensive telehealth visits at a fixed rate — no membership fees, no insurance required, and no unexpected charges. Whether you’re newly diagnosed or looking for a provider who actually listens, we’re here to help.
