<p>Epilepsy is a common neurological disorder in childhood, and levetiracetam, a newer anti-seizure medication (ASM), is widely used due to its efficacy and safety. Recent attention has focused on the effects of anti-seizure medication (ASM) on thyroid function. This study aimed to evaluate changes in thyroid function and thyroid volume in children receiving levetiracetam monotherapy. It is the first study to assess both thyroid function tests and ultrasonographic thyroid volume in this context. In this single-center, prospective study, 40 children aged 3&#xa0;months to 18&#xa0;years with epilepsy who began levetiracetam monotherapy at Dr. Behçet Uz Children’s Hospital between January and June 2024 were included. Thyroid function tests (fT3, fT4, TSH, Anti-TPO, Anti-Tg) and thyroid volume (via ultrasound) were measured before treatment and at the 6th month, and analyzed using age-adjusted standard deviation scores (SDS). No statistically significant differences were found between baseline and 6th-month values for fT3 (<i>p</i> = 0.678), fT4 (<i>p</i> = 0.604), TSH (<i>p</i> = 0.210), Anti-TPO (<i>p</i> = 0.923), or Anti-Tg (<i>p</i> = 0.843). Thyroid volume showed no significant change (<i>p</i> = 0.159), but thyroid volume SDS decreased significantly (<i>p</i> = 0.018). <i>Conclusion</i>: Levetiracetam monotherapy over six months did not significantly affect thyroid hormone levels, autoantibodies, or absolute thyroid volume, although a decrease in thyroid volume SDS was noted. This may be due to measurement variability. Overall, short-term levetiracetam use appears safe in terms of thyroid function.<Table Float="No" ID="Taba"> <tgroup align="left" cols="2"> <colspec align="left" colname="c1" colnum="1" /> <colspec align="left" colname="c2" colnum="2" /> <tbody> <row> <entry nameend="c2" namest="c1"> <p><b>What Is Known:</b></p> <p><i>•&#xa0;</i><i>Levetiracetam is widely used in pediatric epilepsy and is considered to have a favorable safety profile with respect to endocrine function.</i></p> <p><i>•&#xa0;</i><i>Previous studies suggest that levetiracetam has minimal effects on thyroid function in children, although the available data are limited</i><i>.</i></p> <p><b>What Is New:</b></p> <p><i>•&#xa0;</i><i>This prospective study evaluates both thyroid function tests and ultrasonographic thyroid volume in children receiving levetiracetam monotherapy.</i></p> <p><i>•&#xa0;</i><i>Over a six-month follow-up period, thyroid hormone levels and autoantibody profiles remained stable, with no clinically relevant change in absolute thyroid volume, although a mild decrease in thyroid volume standard deviation score was observed.</i></p> </entry> </row> </tbody> </tgroup> </Table></p>