THYROID EVALUATION IN PATIENT USING CARBAMAZEPINE
Keywords:
Carbamazepine, epilepsy, thyroid hormonesAbstract
Review of the relevant literature indicates that carbamazepine may reduce serum leveis of thyroid hormones. lt is not estab/ished if that reduction is due to an increased hormonal metabolism, ar due to the fact that carbamazepine changes triiodotironina and thyroxine from its binding proteins. One study suggests that hormonal changes caused by carbamazepine use, do not lead to clinica/ symptoms. This paper reports the case of a 54 years o/d female outpatient, suffering from epileptic crises, who has been treated with carbamazepine. After 12 years taking the medication, her /ab exams indicated low serum levei of free thyroxine, with normal leve/ of thyroid-stimulating hormone. The clinica/ case presents no change in thyroid-stimulating hormone leve/, and reduced free thyroxine. These findings are in agreement with most studies reviewed. However, in such studies there is nota consensus on the reason why a reducfíon in free thyrox,ne âoes not lead to thyroid-stimulating hormone increase. Nevertheless, authors suggest that hormonal replacement therapy in carbamazepine users must be dane with caution, analyzing thyroid-stimulating hormone leveis and going through a careful clinica/ evaluation of the patients.
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