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[Severe hyponatremia during treatment with fluoxetine]
Revista Medica De Chile
|August 7, 1999
Summary
Selective serotonin reuptake inhibitors (SSRIs) can cause hyponatremia, a dangerous drop in sodium levels, particularly in older adults. This case highlights the importance of monitoring sodium levels when prescribing SSRIs like fluoxetine.
Area of Science:
- Geriatric Medicine
- Clinical Pharmacology
- Endocrinology
Background:
- Selective serotonin reuptake inhibitors (SSRIs) are commonly prescribed antidepressants.
- Hyponatremia, or low blood sodium, is a potential adverse effect linked to SSRIs, especially in the elderly.
- Syndrome of Inappropriate Antidiuretic Hormone (SIADH) secretion is the suspected mechanism.
Observation:
- A 76-year-old female with existing cardiovascular conditions was prescribed fluoxetine.
- Within five days of initiating fluoxetine, she developed confusion, gait instability, and tremors.
- Initial laboratory results revealed severe hyponatremia with a plasma sodium level of 115 meq/L.
Findings:
- Discontinuation of fluoxetine and fluid restriction led to clinical improvement.
- The patient's plasma sodium levels normalized following the intervention.
- This case underscores the association between fluoxetine and hyponatremia in an elderly patient.
Implications:
- Clinicians should maintain a high index of suspicion for SSRI-induced hyponatremia in elderly patients presenting with neurological symptoms.
- Monitoring serum electrolytes is crucial when initiating or adjusting SSRI therapy in this population.
- Early recognition and management can prevent severe complications associated with hyponatremia.
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