Which electrolyte disturbance is commonly associated with oxcarbazepine and carbamazepine?

Oxcarbazepine and carbamazepine are both anticonvulsant medications that can lead to a condition known as hyponatremia, which is a lower-than-normal sodium concentration in the blood. This occurs primarily due to the enhancement of antidiuretic hormone (ADH) secretion or action, leading to increased water retention and dilution of serum sodium levels.

Patients taking these medications may not exhibit any symptoms until the sodium levels drop significantly, but when symptoms do occur, they can range from mild (headaches, lethargy) to severe (confusion, seizures, and coma). Monitoring serum sodium levels in patients on these medications is therefore critical.

While other electrolyte disturbances are noted with various medications, the specific association of oxcarbazepine and carbamazepine with hyponatremia is well-documented in clinical literature.