Does hydroxyzine exacerbate hyponatremia (low sodium levels in the blood)?

From the Guidelines

Hydroxyzine is not typically associated with worsening hyponatremia, but caution may be warranted in susceptible individuals. While there's no strong evidence linking hydroxyzine directly to hyponatremia, it's always prudent to monitor sodium levels in patients at risk, especially when starting new medications. Hydroxyzine, an antihistamine commonly used for anxiety and allergies, does not have a known significant effect on sodium balance. However, in patients with pre-existing hyponatremia or those at high risk (e.g., elderly, those on diuretics, or with conditions like SIADH), it's advisable to monitor sodium levels periodically. The theoretical concern stems from the mild anticholinergic effects of antihistamines, which could potentially influence fluid balance, albeit minimally. If hydroxyzine is necessary for a patient with hyponatremia, start with a low dose and titrate carefully while monitoring sodium levels. Always consider the overall medication regimen and underlying conditions when assessing the risk of hyponatremia.

Key Considerations

• The management of hyponatremia in patients with cirrhosis involves inducing a negative water balance to improve serum sodium concentration 1.
• Vaptans, such as tolvaptan, have been shown to be effective in improving serum sodium concentration in patients with hypervolemic hyponatremia, but should be used with caution and close monitoring 1.
• Fluid restriction and hypertonic sodium chloride administration may be considered in certain cases, but should be used judiciously and with careful monitoring 1.
• The overall medication regimen and underlying conditions should be taken into account when assessing the risk of hyponatremia in patients taking hydroxyzine 1.

Recommendations

• Monitor sodium levels periodically in patients at risk of hyponatremia, especially when starting new medications like hydroxyzine.
• Start with a low dose and titrate carefully while monitoring sodium levels if hydroxyzine is necessary for a patient with hyponatremia.
• Consider the overall medication regimen and underlying conditions when assessing the risk of hyponatremia.

From the Research

Hyponatremia and Hydroxyzine

• There is no direct evidence in the provided studies that hydroxyzine exacerbates hyponatremia (low sodium levels in the blood) 2, 3, 4, 5, 6.
• The studies discuss various medications that can cause hyponatremia, including antiseizure medications, psychotropic medications, diuretics, antidepressants, and antiepileptics 2, 3, 4, 5.
• Hydroxyzine is not mentioned as a medication that can cause or exacerbate hyponatremia in any of the provided studies.
• The management of hyponatremia is discussed in the studies, including treatment options and risk factors for developing hyponatremia 3, 4, 5, 6.

Risk Factors and Treatment

• Risk factors for developing hyponatremia include age, gender, dosage, and combinations with other drugs 2.
• Treatment options for hyponatremia vary based on the degree of severity and include cessation of the offending medication, cation repletion, and oral fluid restriction 6.
• In severe cases, 3% saline solution may be indicated, but overly rapid correction of chronic hyponatremia must be avoided 6.

Medications that Can Cause Hyponatremia

• Antiseizure medications such as carbamazepine, oxcarbazepine, and valproic acid have a higher risk of causing hyponatremia 2.
• Psychotropic medications, including SSRIs, SNRIs, antipsychotics, carbamazepine, and oxcarbazepine, have been implicated in the etiology of drug-induced SIADH 4.
• Diuretics, antidepressants, and antiepileptics have also been established as causes of hyponatremia 5.