A condition resulting from an excess of thyroid hormones, usually due to excessive production.
Causes
- Grave’s disease (autoimmune, common in females)
- Neonatal thyrotoxicosis
- Tumours of thyroid gland (adenomas, multinodular toxic goiter)
- Inflammation of the thyroid gland (thyroiditis)
- Iatrogenic causes (side effect of some medications)
Clinical features
- Weight loss with increased appetite
- Swelling in the neck (goitre)
- Palpitations, tachycardia
- Irritability, nervousness, inability to rest or sleep
- Irregular, scanty menstrual periods
- Profuse sweating, extreme discomfort in hot weather
- High blood pressure
- Protruding eyes (exophthalmos) in some forms
- Frequent defecation
Differential diagnosis
- Anxiety states
- Tumours of the adrenal gland (pheochromocytoma)
- Other causes of weight loss
- Other causes of protruding eyes
Investigations
- Blood levels of thyroid hormone (high T3, T4, low TSH)
- Thyroid ultrasound scan
- Biopsy of thyroid gland for cytology/histology
Management
The aim is to restore the euthyroid state Use pulse rate and thyroid hormones level to monitor
progress
- Carbimazole 15-40 mg (max 60 mg) in 2-3 divided doses for 1-2 months
Child: 750 micrograms/kg/day in divided doses (max 30 mg)- Adjust dose according to thyroid hormone levels (under specialist management only)
To control excessive sympathetic symptoms (e.g. palpitations), add:
- Propranolol 40-80 mg every 12 hours for at least 1 month
Child: 250-500 micrograms/kg 3-4 times daily
Once patient is euthyroid
- Stop propranolol, and progressively reduce carbimazole to daily maintenance dose of 5-15
mg. Continue carbimazole for at least 18 months - Surgery may be required in certain cases, e.g., obstruction, intolerance, or lack of response to
drug treatment - Radioactive iodine may also be used especially in toxic multinodular goitre
Caution
- Patients treated with carbimazole should be advised toreport any sore throat immediately because of the rare
complication of agranulocytosis (low white cell count)