Does Escitalopram (Lexapro) cause hyponatremia?

From the Guidelines

Lexapro can cause hyponatremia, with a risk of 0.5% to 12% in older adults, as reported in a case-control study 1. This is a recognized side effect of selective serotonin reuptake inhibitors (SSRIs) like Lexapro. The risk is higher in older adults, with an odds ratio of 3.3 (95% CI, 1.3 to 8.6) for SSRIs compared with other drug classes 1. Hyponatremia typically develops within the first month of starting the medication, but can occur at any time during treatment. The mechanism involves the SSRI enhancing the effects of antidiuretic hormone (ADH), leading to increased water retention and dilution of sodium in the bloodstream. Some key points to consider include:

• The risk of hyponatremia is higher in older adults, with a risk range of 0.5% to 12% 1
• The odds ratio for SSRIs, including Lexapro, is 3.3 (95% CI, 1.3 to 8.6) compared with other drug classes 1
• Hyponatremia can develop within the first month of starting the medication, but can occur at any time during treatment 1 Symptoms of hyponatremia may include headache, confusion, fatigue, muscle weakness, seizures, and in severe cases, coma. Patients taking Lexapro should be aware of these potential symptoms and seek medical attention if they develop. Regular monitoring of sodium levels may be recommended, especially for those at higher risk. If hyponatremia occurs, treatment may involve adjusting the Lexapro dosage, switching to a different antidepressant, or in severe cases, discontinuing the medication under medical supervision.

From the FDA Drug Label

Hyponatremia may occur as a result of treatment with SSRIs and SNRIs, including Escitalopram. In many cases, this hyponatremia appears to be the result of the syndrome of inappropriate antidiuretic hormone secretion (SIADH), and was reversible when Escitalopram was discontinued. Cases with serum sodium lower than 110 mmol/L have been reported Elderly patients may be at greater risk of developing hyponatremia with SSRIs and SNRIs. Also, patients taking diuretics or who are otherwise volume depleted may be at greater risk [see Geriatric Use (8. 5)].

Yes, Lexapro (escitalopram) may cause hyponatremia.

• The condition is potentially reversible upon discontinuation of the medication.
• Elderly patients and those taking diuretics or who are volume depleted may be at greater risk.
• Signs and symptoms of hyponatremia include headache, difficulty concentrating, memory impairment, confusion, weakness, and unsteadiness, which may lead to falls 2.

From the Research

Lexapro and Hyponatremia

• Lexapro, also known as escitalopram, is a selective serotonin reuptake inhibitor (SSRI) used to treat depression and anxiety disorders.
• There have been reports of hyponatremia associated with the use of SSRIs, including escitalopram 3, 4, 5, 6, 7.
• Hyponatremia is a condition characterized by low sodium levels in the blood, which can be caused by the syndrome of inappropriate antidiuretic hormone secretion (SIADH) 3, 6.
• The risk of hyponatremia is higher in older adults, especially those taking multiple medications, including diuretics 4, 7.
• Studies have shown that SSRIs, including escitalopram, can cause SIADH, leading to hyponatremia 3, 5, 6, 7.
• The incidence of hyponatremia associated with SSRIs, including escitalopram, varies widely, ranging from 0.06% to 40% 7.
• It is essential to monitor sodium levels regularly in patients taking escitalopram, especially in older adults with multiple comorbidities and polypharmacy 4, 5, 7.

Risk Factors

• Older age is a significant risk factor for developing hyponatremia while taking escitalopram 4, 7.
• Concomitant use of diuretics, such as thiazides, increases the risk of hyponatremia 4, 7.
• Patients with multiple comorbidities and polypharmacy are also at higher risk of developing hyponatremia while taking escitalopram 5.

Clinical Implications

• Clinicians should be aware of the risk of hyponatremia associated with escitalopram and monitor sodium levels regularly in high-risk patients 4, 7.
• Alternative treatments, such as bupropion, may be considered for patients at risk of hyponatremia 4.
• Regular monitoring of electrolytes, especially sodium levels, is crucial in patients taking escitalopram, especially in older adults 6.