Effect of prolonged administration of gliclazide on the thyroid function in rabbits

ABSTRACT

Gliclazide [Diamicron] is an oral hypoglycemic drug which belongs to the sulphonylurea compounds. Gliclazide was administered orally to male rabbits in a dose of 200 micro g/Kg/day. The drug was suspended in gum acacia mucilage [1%] in a concentration of 200 micro g/ml. Each of the control rabbits received 1.0 ml gum acacia mucilage [1%] orally. Treatment was performed daily for four weeks, then blood was collected for the determination of the levels of thyroid stimulating hormone [TSH], triiodothyronine [T[3]] and thyroxine [T[4]]. Treatment with gliclazide resulted in a significant decrease in the levels of TSH and T[3] and a non significant decrease in T[4]. Possible mechanisms underlying this antithyroid effect of gliclazide are then discussed