Symptoms of Hyperthyroidism
- Weight loss despite good or increased appetite
- Palpitations, rapid heartbeat (tachycardia), atrial fibrillation
- Heat intolerance, excessive sweating
- Tremor (fine resting tremor of outstretched hands)
- Anxiety, irritability, insomnia
- Diarrhoea or increased bowel frequency
- Goitre (enlarged thyroid) — especially in Graves'
- Thyroid eye disease (Graves' ophthalmopathy) — proptosis, lid retraction, diplopia
Causes
| Cause | Features | Treatment |
|---|---|---|
| Graves' disease | Autoimmune; TRAb-positive; diffuse goitre; eye disease | Antithyroid drugs, radioiodine, or thyroidectomy |
| Toxic multinodular goitre | Older patients; palpable nodules; no TRAb | Radioiodine preferred or surgery |
| Toxic adenoma | Single 'hot' nodule; low TSH; TRAb negative | Radioiodine or surgical excision |
| Thyroiditis (subacute) | Post-viral; painful thyroid; transient hyperthyroid then hypothyroid | NSAIDs/steroids; usually resolves spontaneously |
| Amiodarone-induced | Drug with high iodine content | Requires specialist management |
Thyroid StormRare but life-threatening — fever, tachycardia, confusion, vomiting, AF. Precipitated by illness, surgery, or iodine exposure. ICU management required: PTU, propranolol, iodine, steroids, supportive care.
What is carbimazole?
The most commonly used antithyroid drug in the UK. It blocks thyroid hormone synthesis. Titrate-and-block or block-and-replace regimens are used. Monitor for agranulocytosis (sore throat, fever → stop drug, check WBC urgently).
Can hyperthyroidism cause atrial fibrillation?
Yes. Excess thyroid hormone sensitises the heart to catecholamines, causing AF in up to 10–15% of hyperthyroid patients. AF often resolves when euthyroid state is restored — but anticoagulation may be needed during this period.
Is radioiodine safe?
Yes. I-131 is the most common treatment for Graves' disease worldwide. It destroys overactive thyroid tissue. Most patients develop hypothyroidism afterwards and need levothyroxine — this is expected and manageable.
Can hyperthyroidism go away on its own?
Graves' disease has a remission rate of ~30–50% after 12–18 months of antithyroid drug therapy. Toxic nodules and multinodular goitre rarely remit spontaneously.
Medical Disclaimer: This page is for general education only and does not replace professional medical advice. Always consult a qualified healthcare provider.