Drugs are one of the causes implicated in the development of lowering of sodium level or hyponatremia.(4✔)
Drugs that cause hyponatremia include:
Diuretics affect the balance between sodium and water and are among the most common drugs implicated in the development of hyponatremia.
Among these, the selective serotonin uptake inhibitors are particularly implicated in causing hyponatremia.
Antidepressant and antipsychotic drugs cause hyponatremia through the development of SIADH.
Carbamazepine, oxcarbazepine and sodium valproate cause an increase in production of ADH, whereas carbamazepine and lamotrigine cause potentiation of ADH effect. Oxcarbazepine has been found to cause hyponatremia more commonly as compared to carbamazepine.
The anticancer drugs increase the release of ADH. Cyclophosphamide in addition potentiates the effect of ADH. Vincristine and vinblastine exert a direct effect on the hypothalamus and pituitary to increase the release of ADH. Cisplatin probably causes hyponatremia by causing SIADH and through its effect on the kidneys.(5✔)
Opiates bring about hyponatremia by stimulating ADH release directly or indirectly by causing nausea or low blood pressure. Nonsteroidal anti-inflammatory drugs potentiate the effect of ADH.
Chlorpropamide causes SIADH whereas tolbutamide decreases clearance of free water by the kidneys.
Deamino-D-arginine vasopressin (DDAVP) and oxytocin prevent the excretion of water by the kidneys, thus can cause hyponatremia especially when administered with electrolyte-free water.
Other drugs that could rarely cause hyponatremia include: