Hypothalamic pituitary function testing on children receiving carbamazepine or sodium valproate.

Area of Science:

• Pediatric Endocrinology
• Neuroendocrinology
• Pharmacology

Background:

• Epilepsy is common in children and adolescents.
• Carbamazepine (CBZ) and sodium valproate (NaV) are frequently used as monotherapy for epilepsy.
• The hypothalamic pituitary axis (HPA) is crucial for growth and development.

Purpose of the Study:

• To investigate the long-term effects of CBZ and NaV monotherapy on HPA function in pediatric patients.
• To assess hormonal responses including thyroid, growth hormone, and reproductive hormones.

Main Methods:

• Evaluated HPA axis function in children and adolescents on long-term CBZ or NaV monotherapy.
• Measured thyroid hormones (total T4, free T4, T3), TSH response to TRH, GH response to arginine/L-Dopa, and basal cortisol.
• Assessed luteinising hormone, prolactin, testosterone, and oestradiol in post-pubertal individuals.

Main Results:

• A significant reduction in total T4 was observed in the CBZ group.
• Free T4, T3, and TSH response to TRH were similar between CBZ and NaV groups.
• Adequate growth hormone response and normal basal cortisol levels were noted in all patients.
• Appropriate hormonal responses (LH, prolactin, testosterone, oestradiol) were seen in post-pubertal subjects.

Conclusions:

• Long-term monotherapy with CBZ or NaV in children and adolescents does not appear to compromise overall HPA function.
• While some thyroid hormone changes occur with CBZ, critical HPA functions remain intact.
• These findings support the continued use of CBZ and NaV in pediatric epilepsy management regarding HPA axis safety.