Treatment Options for Hyperthyroidism
The primary treatment options for hyperthyroidism include antithyroid medications, radioactive iodine ablation, and surgical thyroidectomy, with the choice depending on the underlying cause, severity of symptoms, and patient-specific factors. 1
Diagnosis and Evaluation
Before initiating treatment, proper diagnosis is essential:
- Confirm hyperthyroidism with laboratory tests: suppressed TSH with elevated free T4 and/or T3 levels
- Determine etiology through:
- Clinical assessment
- TSH-receptor antibody testing
- Thyroid ultrasonography
- Radionuclide thyroid scintigraphy (if etiology unclear or nodules present)
Treatment Options by Cause
1. Graves' Disease (70% of hyperthyroidism cases) 2
First-line treatment: 12-18 month course of antithyroid drugs 1
- Methimazole (MMI) is preferred over propylthiouracil (PTU) due to:
- Longer half-life
- Fewer severe side effects
- More convenient dosing 3
- PTU is preferred only during first trimester of pregnancy 4
- Recurrence rate after short-term treatment: approximately 50% 2
- Long-term treatment (5-10 years) reduces recurrence to about 15% 2
- Methimazole (MMI) is preferred over propylthiouracil (PTU) due to:
Second-line options:
- Radioactive iodine (RAI) ablation (most widely used in US) 5
- Thyroidectomy
2. Toxic Nodular Goiter (16% of cases) 2
- Preferred treatments:
3. Thyroiditis (Destructive Thyrotoxicosis)
- Usually mild and transient
- Management:
Graded Management Approach for Hyperthyroidism 7
Grade 1 (Asymptomatic or mild symptoms)
- Can continue normal activities
- Beta-blocker (e.g., atenolol or propranolol) for symptomatic relief
- Monitor thyroid function every 2-3 weeks after diagnosis
Grade 2 (Moderate symptoms)
- Consider beta-blockers for symptomatic relief
- Hydration and supportive care
- For persistent thyrotoxicosis (>6 weeks), consider medical thyroid suppression
Grade 3-4 (Severe symptoms)
- Beta-blocker therapy
- Hydration and supportive care
- Consider hospitalization in severe cases
- Endocrine consultation
- May require additional therapies including steroids, potassium iodide, or thionamides
Special Considerations
Pregnancy 7
- Hyperthyroidism in pregnancy is treated with thioamides:
- Propylthiouracil preferred in first trimester
- Goal: maintain FT4 or FTI in high-normal range using lowest possible dosage
- Monitor FT4 or FTI every 2-4 weeks
- Beta-blockers can be used temporarily until thioamide therapy reduces hormone levels
- Thyroidectomy reserved for women who don't respond to thioamide therapy
- Radioactive iodine (I-131) is contraindicated during pregnancy
Thyroid Storm (Medical Emergency)
- Presents with fever, tachycardia, altered mental status, vomiting, diarrhea, cardiac arrhythmia
- Treatment includes:
- Propylthiouracil or methimazole
- Potassium/sodium iodide solutions
- Dexamethasone
- Beta-blockers
- Supportive care (oxygen, antipyretics, monitoring) 7
Potential Complications of Treatment
Antithyroid Medications
- Severe liver problems (can lead to liver failure, transplant need, or death) 4
- Low white blood cell counts (within first 3 months)
- Agranulocytosis (presents with sore throat and fever)
- Other side effects: hepatitis, vasculitis, thrombocytopenia 7
Radioactive Iodine
- Permanent hypothyroidism requiring lifelong thyroid hormone replacement
- Cannot be used during pregnancy or breastfeeding
Surgery
- Risks of anesthesia
- Potential damage to parathyroid glands or recurrent laryngeal nerve
- Permanent hypothyroidism requiring lifelong thyroid hormone replacement
Long-term Monitoring
- Regular monitoring of thyroid function is essential regardless of treatment choice
- Patients should be educated about symptoms of both hyperthyroidism and hypothyroidism
- Prompt treatment of recurrent disease is important as untreated hyperthyroidism is associated with increased mortality 2