Hashimoto's Thyroiditis: The Most Common Autoimmune Disease
Hypothyroidism of immune origin
Dr. Élodie Bernard
Endocrinologist
In simple terms
Fatigue, weight gain, cold intolerance: recognizing the signs and finding the right levothyroxine dosage.
An autoimmune attack on the thyroid
Hashimoto's thyroiditis is the most common cause of hypothyroidism in countries with sufficient iodine intake. The immune system produces anti-TPO and anti-thyroglobulin antibodies that gradually destroy thyroid tissue.
Symptoms
- Persistent fatigue, somnolence
- Unexplained weight gain, cold intolerance
- Dry skin, hair loss, brittle nails
- Constipation, intellectual slowness
- Menstrual cycle disorders, infertility
- Painless goiter sometimes palpable
Therapeutic solutions
Levothyroxine (Levothyrox, L-Thyroxin): replacement hormone to be taken on an empty stomach, 30 minutes before breakfast. The dose is adjusted by TSH measurement every 6 to 8 weeks until equilibrium, then annually.
Selenium: supplementation (200 µg/day) can reduce anti-TPO antibody titers.
Monitoring: check TSH once a year, adjust the dose during pregnancy (increased needs by 30-50%).
The words explained
Medical terms used above, in everyday language.
- Symptom
- A sign you can feel or see that something is wrong, like pain, tiredness or a rash.
- Hormone
- A chemical messenger made by your body that tells organs what to do.
- Immune system
- Your body's defence team: cells that fight germs and repair damage.
- Antibody
- A protein your body makes to recognise and neutralise a specific germ.
When should you see a doctor?
- Your symptoms last more than a few weeks or keep coming back.
- They get worse quickly, or stop you doing everyday things.
- You notice sudden pain, breathing trouble, fainting or bleeding — seek urgent care.
- You already take medication and want to change anything about it.
This article explains general health information. It does not replace advice from your own doctor.
Frequently asked questions
- What is Hashimoto's Thyroiditis: The Most Common Autoimmune Disease?
- Fatigue, weight gain, cold intolerance: recognizing the signs and finding the right levothyroxine dosage.
- What are the main symptoms or signs of Hashimoto's Thyroiditis: The Most Common Autoimmune Disease?
- Common signs vary from person to person. The article above lists the symptoms to watch for, how they progress, and when they need medical attention.
- When should you see a doctor for Hashimoto's Thyroiditis: The Most Common Autoimmune Disease?
- See a doctor if symptoms last more than a few weeks, get worse quickly, stop you doing everyday things, or if you notice sudden pain, breathing trouble, fainting or bleeding.
Related health topics
Diabetes & Endocrinology
Thyroid Disorders: When the Butterfly Gland Goes Awry
Fatigue, weight gain, nervousness, palpitations: thyroid disorders are common but often unrecognized. A simple blood test can reveal everything.
Diabetes & Endocrinology
An underactive thyroid: symptoms that are easy to miss
Why hypothyroidism is often mistaken for stress or ageing, and how it is confirmed.
Diabetes & Endocrinology
Graves' disease: autoimmune hyperthyroidism
Antithyroid drugs, radioactive iodine, surgery: three options against Graves' disease.