Terbutaline sulfate is a β2 adrenergic agonist agent used in treatment of asthma. Terbutaline’s adverse effects such as skeletal muscle tremor, tachycardia, hyperglicemia and various metabolic effects are mediated by beta-adrenoceptor stimulation .Terbutaline is not recommend use for children younger than 2 years of age.The case of a 44-day-old girl who experienced focal seizure following oral terbutaline sulfate use is presented.For exclusion of other causes of focal seizure, we used brain magnetic resonance imaging, and electroencephalography and it is concluded that focal seizure developed as a result of terbutaline sulfate use