Thyroid function and volume in epileptic children using carbamazepine, oxcarbazepine and valproate.
BACKGROUND
The aim of the present study was to investigate the effects of carbamazepine (CBZ), oxcarbazepine (OXC), and valproic acid (VPA) on thyroid function and volume in epileptic children.


METHODS
Fifty-three epileptic children (age, 3-17 years) treated with OXC (n = 10), CBZ (n = 12), or VPA (n = 31) at least for 1 year were evaluated in terms of thyroid hormones, thyroid-stimulating hormone (TSH) levels, response to thyrotropin-releasing hormone (TRH) stimulation test, and thyroid volumes.


RESULTS
The patients in the OXC and CBZ groups had similar total thyroxin (TT4) and free T4 (fT4) median levels that were significantly lower than those of the VPA group (P < 0.016). Total tri-iodothyrosin median levels were lower in the CBZ group compared to the VPA group (P < 0.016). Basal TSH levels and thyroid volumes were similar in all groups (P > 0.016). One child from the OXC group (10%), one from the CBZ group (%8.3), and six from the VPA group (19.3%) had hypothyroidic status according to the TRH stimulation test. No statistically significant correlations were found between thyroid gland volume and thyroid function variables and between anti-epileptic drug receiving time and thyroid function or thyroid volume, respectively, in any of the groups (P > 0.05).


CONCLUSIONS
Thyroid function should be evaluated periodically in children using CBZ, OXC or VPA. The children taking VPA seems to be at greater risk compared to children onr CBZ or OXC therapy. Except for the basal TSH values in the VPA group, the parameters predictive for the subclinical hypothyroid status remain to be evaluated in further studies.
Department of Pediatric Neurology, Faculty of Medicine, Gazi University, Ankara, Turkey. tluleci13@yahoo.com
Tugba
T
Hirfanoglu
Ayse
A
Serdaroglu
Orhun
O
Camurdan
Ali
A
Cansu
Aysun
A
Bideci
Peyami
P
Cinaz
Kivilcim
K
Gucuyener
D000293:Adolescent; D000927:Anticonvulsants / Q000494:pharmacology* / Q000627:therapeutic use; D002220:Carbamazepine / Q000031:analogs & derivatives* / Q000494:pharmacology* / Q000627:therapeutic use; D002648:Child; D002675:Child, Preschool; D004827:Epilepsy / Q000188:drug therapy / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007037:Hypothyroidism / Q000139:chemically induced / Q000175:diagnosis; D008297:Male; D009929:Organ Size / Q000187:drug effects; D000078330:Oxcarbazepine; D013960:Thyroid Function Tests; D013961:Thyroid Gland / Q000033:anatomy & histology / Q000187:drug effects* / Q000502:physiology; D013972:Thyrotropin / Q000097:blood*; D014635:Valproic Acid / Q000494:pharmacology* / Q000627:therapeutic use
D000927:Anticonvulsants; D002220:Carbamazepine; D014635:Valproic Acid; D013972:Thyrotropin; D000078330:Oxcarbazepine