ABSTRACT

We aimed to determine the hyponatremia rate and risk factors related to carbamazepine (CBZ) and oxcarbazepine (OXC) treatment.

We examined sodium (Na) concentrations in 52 OXC- and 142 CBZ- treated patients with epilepsy using a retrospective study.

The frequency of hyponatremia (Na ≤134 mEq/L) was 11.5% among OXC-treated patients and 5.6% among CBZ-treated patients. Hyponatremia (Na ≤128 mEq/L) was severe in 3.8% of OXC-treated patients and 1.4% of CBZ-treated patients. Most patients with CBZ/OXCinduced hyponatremia were asymptomatic.

It was determined that the frequencies of hyponatremia and severe hyponatremia were higher in the OXC group than in the CBZ group. Most of the patients were asymptomatic and did not need treatment. Although risk factors in previous studies did not reach significant statistical value because of the low number of patients with hyponatremia, it is suggested to follow serum Na values when risk factors are present.

Keywords: Hyponatremia, carbamazepine, oxcarbazepine, adverse effect