Hyperthyroidism (Overactive Thyroid)

When your thyroid makes and releases high levels of thyroid hormone, you have hyperthyroidism, also known as an overactive thyroid. It accelerates many body processes, leading to symptoms like anxiety, weight loss, elevated appetite, and a fast heartbeat. It is possible to treat hyperthyroidism, typically with medication.

What is Hyperthyroidism?

Hyperthyroidism, or overactive thyroid, occurs when the thyroid makes and releases excessive amounts of thyroid hormone. Multiple possible causes exist. Triiodothyronine (T3), thyroxine (T4), and thyroid-stimulating hormone (TSH) are the three primary thyroid hormones.

Your metabolism is accelerated by hyperthyroidism, which can have an impact on a number of your health issues. The condition has the potential to upset your entire equilibrium. It's possible that you don't feel like yourself or that your body is out of control. If you have symptoms of hyperthyroidism, it's critical to get medical attention so you can get back to your normal self-esteem.

When your thyroid, the butterfly-shaped gland located at the base of your neck, just above your collarbone, produces too much thyroid hormone, it is known as hyperthyroidism. An overabundance disrupts your entire system because your body needs specific amounts of the substance to function properly. You may notice changes in your hair, eyesight, heart rate, temperament, and weight, among other consequences.

Usually, an overactive thyroid usually requires assistance to correct itself. Medication and, in certain situations, surgery will be needed to address it.

Also Read: Hypothyroidism (Underactive Thyroid)

What symptoms are present in hyperthyroidism?

The symptoms of hyperthyroidism are numerous and can affect every part of your body. You can have a combination of these symptoms, or you might only have part of them. The following are some signs of hyperthyroidism:

• Tachycardia, or an elevated heart rate, and/or palpitations.

• High blood pressure.

• Hand tremors make you shaky.

• Experiencing agitation, nervousness, and/or anxiety.

• Fragile hair or hair loss.

• Difficulty falling asleep (insomnia).

• Menstrual cycle variations, such as lighter or absent periods.

• Neck growth and swelling (goiter).

• Eye bulging or swelling (thyroid eye illness).

These symptoms may appear gradually over time or may begin abruptly. If you experience signs of hyperthyroidism, it's critical to consult your doctor.

Causes:

The following illnesses and circumstances can result in hyperthyroidism:

• An autoimmune disorder called Graves' disease causes your thyroid to become hyperactive. The most frequent cause of hyperthyroidism is Graves' disease. If thyroid illness and/or another autoimmune ailment runs in your biological family, your chances of getting it are higher.

• Cell growths or lumps in your thyroid gland are called thyroid nodules. Sometimes, they may create too much thyroid hormone. Medical professionals may refer to this condition as toxic multinodular goiter (TMNG). Rarely are thyroid nodules malignant.

• Thyroid disease: Your thyroid gland becomes inflamed when you have thyroiditis. Temporary hyperthyroidism may result from it. Following this stage, known as the thyrotoxic phase, hypothyroidism (underactive thyroid) may result. Your hormone levels may regulate as the inflammation subsides.

• Excessive iodine consumption: Your thyroid may create extra thyroid hormone if you consume too much iodine from diet or medicine. Your thyroid produces thyroid hormone using the mineral iodine. Hyperthyroidism can result after taking amiodarone, a medicine, or from receiving IV iodinated contrast (iodine "dye").

• Thyrotropinoma, or pituitary adenoma that releases TSH: Your pituitary gland is growing and releasing too much thyroid-stimulating hormone (TSH). Normally, the pituitary gland releases TSH, which causes the thyroid to release thyroid hormone. Thyroid hormone excess can result from too much TSH. This is an extremely uncommon reason for hyperthyroidism.

Which variables increase the risk of hyperthyroidism?

The following variables raise your risk of hyperthyroidism:

• Autoimmune disorders and/or thyroid diseases in the biological family.

• Smoking.

• Pregnancy (for postpartum thyroiditis ).

How is a diagnosis of hyperthyroidism made?

There may be multiple steps in the hyperthyroidism diagnostic procedure, including:

• Your doctor will first perform a physical examination to look for symptoms of hyperthyroidism, such as an enlarged thyroid, a fast heartbeat, and warm, wet skin.

• Thyroid blood testing: Your thyroid hormone levels can be determined by blood tests. Thyroid-stimulating hormone (TSH) levels are frequently (though not always) lower than normal in people with hyperthyroidism, whereas levels of the thyroid hormones T3 and T4 are higher than normal.

• Blood test for thyroid antibodies: This test can determine whether Graves' disease is the cause.

• Imaging test: Several thyroid imaging tests can be used to identify the source of hyperthyroidism. These consist of a thyroid ultrasound and a radioactive iodine uptake (RAIU) test and scan. After discussing the options and procedures with you, your provider will suggest the test that they believe is most appropriate.

How may hyperthyroidism be treated?

Treatment options for hyperthyroidism are many. Certain solutions might be better for you than others, depending on the cause. Your healthcare professional will help you choose the best course of action by going over each choice with you.

Antithyroid medications

Propylthiouracil (PTU) and methimazole (Tapazole®) prevent your thyroid from producing hormones. The most popular way to treat hyperthyroidism is with these medications. In two to three months, they can often regulate thyroid function. In a few days to a few weeks, your symptoms might improve.

Treatment with radioactive iodine (RAI)

Radioactive iodine is taken orally as a single capsule or liquid dose during RAI therapy. The radioactive iodine particularly targets and kills your thyroid cells. RAI typically causes your thyroid to be permanently destroyed, curing hyperthyroidism.  To maintain normal thyroid hormone levels, the majority of people who receive this treatment will need to take levothyroxine, a thyroid hormone medication, for the remainder of their lives.



Surgery:

Your thyroid gland may be surgically removed whole or in part (thyroidectomy). Although hyperthyroidism will be corrected, hypothyroidism will typically result, necessitating lifelong thyroid hormone medication.
 The thyroid gland may be removed whole or in part with this procedure. Hyperthyroidism is rarely treated with it. However, pregnant women might be able to use it. For people who are unable to take antithyroid medications or who are unwilling or unable to undergo radioiodine therapy, it can also be an option.

Damage to the parathyroid glands and vocal chords are among the risks associated with this procedure. Four little glands on the rear of the thyroid are called parathyroid glands. They aid in regulating the blood's calcium levels.

Individuals who have radioiodine therapy or thyroidectomy require lifelong levothyroxine (Levoxyl, Synthroid, etc.) treatment. It provides thyroid hormones to the body. Surgery removes the parathyroid glands,

Beta-blockers:

Beta-blockers are medications that help control the symptoms of hyperthyroidism, such as shakiness, nervousness, and a fast heartbeat. However, they do not effect your blood's hormone levels. Beta-blockers could be recommended by your doctor in addition to another treatment.

There are risks and adverse effects associated with each of these treatments. You will review them with your provider. Never be hesitant to ask questions.

References:

• Merck Manual: Consumer Version. Hyperthyroidism (https://www.merckmanuals.com/home/hormonal-and-metabolic-disorders/thyroid-gland-disorders/hyperthyroidism). Last revised 2/2023. Accessed 10/31/2024.

• National Institute of Diabetes and Digestive and Kidney Diseases (U.S.). Thyroid Disease & Pregnancy (https://www.niddk.nih.gov/health-information/endocrine-diseases/pregnancy-thyroid-disease). Last reviewed 12/2017. Accessed 10/31/2024.

• Hyperthyroidism. American Thyroid Association. https://www.thyroid.org/hyperthyroidism/. Accessed Oct. 28, 2022.

• Davies TF, et al. Treatment of thyroid eye disease. https://www.uptodate.com/contents/search. Accessed Oct. 31, 2022.

• American Thyroid Association. Hyperthyroidism (http://www.thyroid.org/hyperthyroidism/). Accessed 10/31/2024.

• Hyperthyroidism. Merck Manual Professional Version. https://www.merckmanuals.com/professional/endocrine-and-metabolic-disorders/thyroid-disorders/hyperthyroidism. Accessed Oct. 28, 2022.

• Graves' disease. National Institute of Diabetes and Digestive and Kidney Diseases. https://www.niddk.nih.gov/health-information/endocrine-diseases/graves-disease. Accessed Oct. 28, 2022.

• McDermott MT. In the clinic: Hyperthyroidism. Annals of Internal Medicine. 2020; doi:10.7326/AITC202004070.