4
Symptomatic Management
Table 2. Beta-Adrenergic Receptor Blockade in the
Treatment of Thyrotoxicosis
Drug Dosage Frequency Considerations
Propanolol
a
10–40 mg tid – qid • Nonselective
β-adrenergic receptor
blockade
• Longest experience
• May block T
4
to T
3
conversion at high
doses
Atenolol 25–100 mg qd or bid • Relative β-1 selectivity
• Increased compliance
• Avoid during
pregnancy
Metoprolol
b
25–50 mg bid – tid • Relative β-1 selectivity
Nadolol 40–160 mg qd • Nonselective
β-adrenergic receptor
blockade
• Once daily
• Least experience to
date
• May block T
4
to T
3
conversion at high
doses
Esmolol IV pump
50–100
µg/kg/min
• In intensive care
unit setting of severe
thyrotoxicosis or storm
a
Each of these drugs has been approved for treatment of cardiovascular diseases, but to date none
has been approved for the treatment of thyrotoxicosis.
b
Also available in once daily preparations.
Symptomatic Management
2. β-adrenergic blockade is recommended in all patients with
symptomatic thyrotoxicosis, especially elderly patients and
thyrotoxic patients with resting heart rates >90 bpm or coexistent
cardiovascular disease. (S-M)
