Summary
The influence of β-adrenoceptor antagonists on serum TSH level (supersensitive method)
and thyroid volume has not previously been studied. Thirty-two young non-smoking males
were treated for 3 weeks with either atenolol 50 mg (b. i. d.), metoprolol 100 mg
(b. i. d.) or propranolol 80 mg (b. i. d.) in a placebo controlled study. After 1
week, median serum TSH level increased in the atenolol (from 1.76 (range: 0.96-4.04)
to 2.25 (range: 1.11-4.22) mU/1, P < 0.05) and propranolol (from 1.91 (range: 0.90-3.83)
to 2.44 (range: 0.75-6.30) mU/1, P < 0.05) treated groups. After 3 weeks, median serum
TSH reached pretreatment level in the atenolol treated, whereas median serum TSH decreased
compared to pretreatment values in the propranolol treated (1.68 (range: 0.68-3.62)
mU/1, P < 0.05). Except for a slight increase in the atenolol treated group, no changes
in median thyroid volume was seen after 3 weeks. The changes in serum TSH or thyroid
volume were not related to changes in the concentrations of thyroid hormones, or of
a magnitude likely to interfere with the clinical evaluation of thyroid function.
Key words
Beta-Adrenoceptor Antagonists - Thyrotropin - Thyroid Hormones - Thyroid Volume
