Preoperative treatment of thyrotoxicosis with a beta-adrenergic blocking agent.

The clinical usefulness of propranolol as the sole drug in the preoperative treatment of thyrotoxicosis has been investigated. The effect of the drug on the serum levels of thyroxine and triiodothyronine has also been studied. Eight consecutive patients were treated. Four of these showed good clinical response to propranolol and both pre- and postoperative periods were uneventful. Two patients also showed a good clinical response but developed accentuated thyrotoxic symptoms in the immediate postoperative period. One patient showed no clinical response to propranolol therapy and in one further patient the treatment was discontinued because of discomfort. All glands were resected without technical difficulty. They were more vascular and friable after this therapy than after pretreatment with antithyroid drugs and thyroxine. The serum levels of thyroxine and triiodothyronine decreased during propranolol treatment. It is concluded that treatment with propranolol as a sole preoperative drug might be used as an alternative only in cases where conventional therapy is not suitable.