Journal of Pediatric Perspectives

Journal of Pediatric Perspectives

Effects of Antiepileptic Monotherapy with Clobazam, Phenobarbital, Carbamazepine, and Levetiracetam on Thyroid Hormone Profiles in Children Aged 2–16 Years

Document Type : original article

Authors
Elika Eqlimi 1
Leila Katebi 1
Aziz Kamran 2
Parisa Ahadi 1
1 Department of Pediatrics, School of Medicine, Bu'ali Hospital, Ardabil University of Medical Sciences, Ardabil, Iran.
2 Department of Community Medicine, School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran.
10.22038/jpp.2026.95644.5653
Abstract
Background: Antiepileptic drugs (AEDs) constitute the cornerstone of epilepsy management in children. However, accumulating evidence suggests that certain AEDs may alter endocrine function, particularly the hypothalamic–pituitary–thyroid axis. Given the critical role of thyroid hormones in growth and neurodevelopment, clarifying the endocrine safety profile of these agents in pediatric populations is clinically essential.
Objective: To evaluate the effects of carbamazepine, phenobarbital, clobazam, and levetiracetam on serum thyroid hormone levels (TSH, FT4, and T3) in children aged 2–16 years over a 6-month treatment period.
Methods: In this prospective before-and-after interventional study, 80 children with epilepsy receiving monotherapy (20 per drug group) were enrolled. Baseline demographic and anthropometric characteristics were comparable across groups. Serum TSH, FT4, and T3 levels, along with weight and height, were measured at treatment initiation and after 6 months. Within-group changes were analyzed using paired t tests, and between-group differences were assessed using one-way analysis of variance (ANOVA). Statistical significance was defined as P < 0.05.
Results: After 6 months, significant alterations in FT4 and T3 levels were observed exclusively in the carbamazepine group (P < 0.05), with mean hormonal changes differing significantly from those in the other treatment groups. No significant thyroid hormone changes were detected in the phenobarbital, clobazam, or levetiracetam groups. Although weight and height increased significantly in all groups (P < 0.01), the magnitude of growth changes did not differ between treatments.
Conclusion: Carbamazepine was associated with measurable alterations in thyroid hormone levels over 6-month, whereas phenobarbital, clobazam, and levetiracetam demonstrated relative short-term endocrine stability. Ongoing thyroid function monitoring may be warranted, particularly in children receiving conventional enzyme-inducing AEDs.
Keywords
Antiepileptic drugs
Carbamazepine
Epilepsy
Levetiracetam
Pediatric
Thyroid function
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Journal of Pediatric Perspectives
Volume 14, Issue 4
April 2026
Pages 20051-20060