Prophylaxis of carbamazepine-induced hyponatremia by demeclocycline in six patients.

BACKGROUND

Hyponatremia has been reported to occur in approximately 5% of carbamazepine-treated patients who otherwise do well on that agent. Demeclocycline has been used in the treatment of hyponatremia of various etiologies including one case of carbamazepine-induced hyponatremia.

METHOD

We extended these observations by studying the effects of demeclocycline on carbamazepine-induced hyponatremia in six psychiatric inpatients.

RESULTS

Once serum sodium concentrations had normalized after carbamazepine discontinuation, demeclocycline prevented further decreases in sodium levels upon rechallenge with carbamazepine in five of six patients. Gender, smoking, and neurologic compromise may have played a role in the development of carbamazepine-induced hyponatremia as well as response to this strategy, although our sample size is too small to make firm conclusions.

CONCLUSION

Demeclocycline was successfully used in the prophylaxis of carbamazepine-induced hyponatremia and may be useful in cases that respond best to carbamazepine treatment.