Background:
Thyrotropin-releasing hormone is an endogenous tripeptide with endocrine-independent neurophysiologic properties that may be relevant to affective or seizure disorders. We studied the effect of carbamazepine, which has both mood-stabilizing and anticonvulsant properties, on cerebrospinal fluid thyrotropin-releasing hormone levels in affectively ill patients.
Method:
Paired cerebrospinal fluid samples were collected from nine inpatients with mood disorders, both while medication free and while taking carbamazepine for an average of longer than 1 month at 950 mg/d, achieving blood levels of 8.8 mg/L.
Results:
Carbamazepine treatment was consistently and significantly associated with increased cerebrospinal fluid thyrotropin-releasing hormone levels (P<.0001).
Conclusion:
As carbamazepine-induced increases in thyrotropin-releasing hormone levels could be relevant to either its psychotropic or anticonvulsant properties, further clinical and preclinical investigation of this finding appears indicated.