Definition:

Thyrotoxicosis is a clinical condition caused by excess thyroid hormones (T3 and T4) in the blood. It may result from various causes, the most common being Graves' disease.

SYMPTOMS

• General/Metabolic: Weight loss despite increased appetite, heat intolerance, fatigue
• Cardiovascular: Palpitations, tachycardia, atrial fibrillation
• Neurological: Anxiety, tremor, irritability, insomnia
• Gastrointestinal: Diarrhoea, increased frequency of bowel movements
• Reproductive: Irregular menstruation, reduced fertility
• Dermatological: Warm, moist skin; hair thinning
• Eye symptoms (in Graves’): Exophthalmos, dry/gritty eyes

COMPLICATIONS:

• Atrial fibrillation → Increased stroke risk
• Heart failure
• Thyroid storm (life-threatening emergency)
• Osteoporosis
• Thyroid eye disease (Graves’)
• Menstrual and fertility issues

TREATMENT OPTIONS:

Antithyroid medications

Block thyroid hormone synthesis

Drugs: Carbimazole, Propylthiouracil

Radioiodine therapy

Oral radioactive iodine to ablate thyroid tissue

Not suitable in pregnancy or severe eye disease

Surgery

Partial or total thyroidectomy

Indicated in large goitre, nodules, or drug intolerance

Beta-blockers

For symptom relief (e.g., palpitations, tremor)

Drugs: Propranolol, Atenolol

FOLLOW-UP AND MONITORING:

• Thyroid function tests (TSH, FT4, FT3): Every 4–6 weeks initially
• Full blood count and liver function tests: Especially if on carbimazole
• Monitor clinical symptoms and side effects regularly
• Watch for hypothyroidism after definitive treatment (radioiodine or surgery) – lifelong levothyroxine may be needed
• Assess for relapse after stopping medications

References:

NICE CKS: Hyperthyroidism (https://cks.nice.org.uk/topics/hyperthyroidism/)

BNF (British National Formulary)

American Thyroid Association Guidelines

-Dr Geranmayeh