From the Research
Gabapentin is associated with a lower risk of hyponatremia compared to other antiepileptic drugs, with an adjusted OR of 1.61 (95% CI, 1.08-2.38) for newly initiated treatment and 0.83 (95% CI, 0.64-1.06) for ongoing treatment 1. Patients taking gabapentin, especially older adults, those on other medications that affect sodium levels, or those with underlying conditions like heart failure or kidney disease, should be monitored for symptoms of hyponatremia. These symptoms include:
- Headache
- Confusion
- Nausea
- Muscle weakness
- Seizures
- In severe cases, coma The mechanism behind gabapentin-induced hyponatremia likely involves inappropriate antidiuretic hormone secretion (SIADH), which causes the body to retain water and dilute sodium levels. If a patient on gabapentin develops hyponatremia, the medication may need to be discontinued or the dose reduced, depending on the severity of the condition and the patient's response. Treatment typically involves fluid restriction and addressing the underlying cause. Healthcare providers should check sodium levels before starting gabapentin and periodically during treatment, especially in high-risk patients. Patients should be educated about the symptoms of hyponatremia and advised to seek medical attention if they experience these symptoms while taking gabapentin. It is essential to note that while gabapentin has a lower risk of hyponatremia, it is still crucial to monitor patients and adjust treatment as needed to minimize the risk of this condition 2. In cases where hyponatremia does occur, vasopressin receptor antagonists may be an effective treatment option, as they have been shown to increase plasma sodium levels in a safe and effective manner 3, 4. However, the use of these antagonists should be carefully considered, and their benefits should be weighed against potential risks, particularly in older adults with chronic kidney disease, who may be at increased risk of adverse events when taking higher doses of gabapentinoids 5.