1994 Volume 41 Issue 6 Pages 717-723
We evaluated the effect of the β-adrenergic receptor blocking agent nadolol on serum levels of free thyroid hormones in 20 untreated patients with Graves' disease, aged between 17 and 57 years (mean±SD, 32.9±10.5). All the patients were treated with 30mg of nadolol alone once-daily for 2 weeks, and clinical and laboratory parameters before and after the treatment were compared. Systolic blood pressure was depressed significantly (P<0.001) from 132.7±11.1 mmHg to 122.8±10.9mmHg. The resting pulse rate was also reduced significantly (from 110.3±9.2/min to 86.0±13.2/min, P<0.001). Serum free thyroxine levels were reduced significantly from 7.1±3.1ng/dl to 5.7±3.6 ng/dl (P<0.05) and serum free triiodothyronine levels were reduced from 21.9±5.6pg/ml to 17.2±6.9pg/ml (P<0.01). In the present study, the β-adrenergic receptor blocking agent nadolol was newly found to have a reducing effect on serum free thyroxine, as well as free triiodothyronine concentrations.