Effect of Propranolol on the Metabolism of Thyroid Hormones

Summary

The effect of propranolol on thyroxine (T₄) and 3,5′,3′-triiodothyronine (T₃ plasma concentrations, fractional disappearance rates (k), metabolic clearance rates (MCR) and catabolic rates has been investigated in young pigs. The animals were examined in the period 18-24 h after feeding. Plasma concentrations of T₃ were lower after treatment with propranolol, but T₄ was not significantly affected. The k value of T₄ was decreased by propranolol but that for T3 was unaffected. The MCR of T₄ and the catabolic rates of both hormones were reduced by propranolol. The reduction in metabolic rate after propranolol is thus probably related to its action on thyroid hormone metabolism.

Thyroid - β-Blocker - Diet-Induced Thermogenesis