Thyroid Emergency Warning Signs
Most thyroid conditions are not emergencies, but a few complications are life-threatening and need immediate care. Knowing the warning signs helps you act quickly.
If you are seriously unwell, do not wait for a routine appointment — seek emergency medical help.
Last medically reviewed: 15 November 2025
Key points
- Thyroid storm is a severe surge of hyperthyroid symptoms — a medical emergency.
- Myxoedema coma is severe hypothyroidism with drowsiness and low temperature.
- A large goitre can compress the airway and cause breathing difficulty.
- Severe low calcium after thyroid surgery needs urgent treatment.
Thyroid storm
Thyroid storm is a rare complication of severe hyperthyroidism, often triggered by infection, surgery, trauma or stopping treatment. Features include high fever, a very fast heart rate, agitation or confusion, vomiting and sometimes heart failure.
It requires emergency hospital treatment.
Myxoedema coma
Myxoedema coma is severe, decompensated hypothyroidism. It causes profound drowsiness or unconsciousness, low body temperature, slow heart rate and low blood sugar, often in an older person with untreated or undertreated hypothyroidism.
It is a medical emergency requiring urgent hormone replacement and supportive care.
Airway compression
A very large goitre or a rapidly enlarging neck mass can press on the windpipe, causing noisy breathing, breathlessness or difficulty lying flat. Bleeding into a nodule can cause sudden enlargement.
Seek emergency care for stridor or severe breathing difficulty.
Severe low calcium after surgery
After thyroid surgery, the parathyroid glands can be disturbed, causing low calcium. Tingling around the mouth or fingers, muscle cramps or twitching can progress to seizures if untreated.
Report these symptoms urgently after surgery.
When to seek urgent medical help
- High fever with a very fast heartbeat, agitation or confusion.
- Profound drowsiness, confusion or a very low body temperature.
- Noisy or difficult breathing, or a rapidly enlarging neck swelling.
- Tingling, cramps or twitching after thyroid surgery.
This guidance does not replace emergency services. If you are seriously unwell, seek urgent medical care immediately.
Frequently asked questions
Is thyroid storm common?
No — it is rare, but it is a medical emergency when it occurs.
What should I do if I suspect thyroid storm?
Seek emergency medical care immediately. Do not wait for a routine appointment.
Can thyroid problems cause breathing difficulty?
A large goitre or neck mass can compress the airway. Breathing difficulty needs urgent assessment.
References & further reading
This page is based on established medical knowledge and guidelines from authoritative sources. Always consult a qualified clinician for personal medical advice.
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