What is Hashimoto’s disease?

Hashimoto’s disease is an autoimmune condition. In Hashimoto’s disease, your body’s immune system attacks your thyroid gland. This stops it from making enough thyroid hormone. This is also called thyroiditis.

Thyroid hormones are important for your metabolism. Low thyroid hormone levels may cause a range of symptoms, such as:

• tiredness
• weight gain
• intolerance to cold temperatures

In some cases, Hashimoto’s disease can cause you to make too much thyroid hormone.

What is the thyroid gland?

Your thyroid gland is a bow-shaped gland at the front of your neck. This gland uses iodine from the food you eat to make thyroid hormones. Thyroid hormones influence important body processes such as body temperature, energy levels and growth.

What are the symptoms of Hashimoto’s disease?

Hashimoto’s disease can slowly cause a lack of thyroid hormones, known as hypothyroidism.

Your symptoms might be mild, or they might be severe. They can include:

• fatigue (tiredness)
• depression or low mood
• weight gain
• constipation
• being unable to stand the cold
• weakness
• muscle pain

Other symptoms can be:

• dry, rough or cold skin
• dry, brittle or thin hair
• low libido
• heavy or irregular periods
• goitre
• breathlessness
• slow heart rate

Hashimoto’s disease can also cause poor concentration and poor memory.

What causes Hashimoto's disease?

Hashimoto’s disease is an autoimmune disease. It happens when your immune system attacks your thyroid gland. This stops it from working properly.

While the cause of Hashimoto's disease is unknown, it may run in families.

When should I see my doctor?

See your doctor if you have a family history of thyroid disease and get symptoms of hypothyroidism.

How is Hashimoto's disease diagnosed?

Your doctor will ask about your symptoms and your medical history. They will also examine you. They will feel the front of your neck to see if your thyroid is swollen.

They may organise for you to have blood tests. These are to check your thyroid hormone levels and measure thyroid antibodies.

Your doctor may refer you to an endocrinologist (a doctor who specialises in hormone conditions).

How is Hashimoto's disease treated?

While there is no cure for Hashimoto's disease, hypothyroidism can be treated. Treatment aims to restore normal body function by replacing your thyroid hormone.

You may need lifelong thyroid hormone replacement treatment with a medicine called levothyroxine (thyroxine). This is a tablet that you take once a day, before breakfast.

You will need to have your thyroid hormone levels tested regularly. This checks that you are getting the right amount of medicine. It’s normal for the dose to be changed at the start of treatment.

What are the complications of Hashimoto's disease?

If left untreated, hypothyroidism can lead to problems including:

• goitre (an increase in the size of the thyroid gland)
• heart problems — such as angina and atrial fibrillation
• osteoporosis
• pregnancy complications — such as pre-eclampsia

Sometimes, it can lead to a potentially life-threatening disorder called myxoedema coma.

Can Hashimoto’s disease be prevented?

Ensuring that you have the correct amount of iodine in your diet can help prevent Hashimoto’s disease.

Resources and support

To learn more about Hashimoto’s disease visit the Australian Thyroid Foundation.

Hormones Australia also offers resources on conditions affecting the thyroid gland.

If you are concerned about Hashimoto’s disease you can call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available to speak with 24 hours a day, 7 days a week.