Apollo doctor warns: Three common medicines that cause dangerously low blood sodium level in the body

Low blood sodium, or hyponatremia, is a potentially serious condition that often goes unnoticed until symptoms become severe. Dr. Sudhir Kumar, MD, a senior neurologist at Apollo Hospitals, Hyderabad, has issued a strict warning regarding the risk of low sodium levels, or hyponatremia, associated with three commonly used medications. According to Dr. Kumar, patients taking these drugs should be vigilant about symptoms such as fatigue, confusion, dizziness, or seizures.

Medicines That Can Trigger Low Sodium
In a post shared on X, Dr. Kumar highlighted three categories of drugs that may significantly lower sodium in the blood, particularly in older adults:

1. Thiazide Diuretics
Medications like hydrochlorothiazide and indapamide, often prescribed for high blood pressure, can increase sodium loss through urine. “They increase sodium loss through urine, especially in elderly patients, leading to fatigue, confusion, or even seizures if sodium drops too low,” Dr. Kumar explained.

2. Selective Serotonin Reuptake Inhibitors (SSRIs)
SSRIs such as sertraline and escitalopram, used to treat depression and anxiety, can raise the release of antidiuretic hormone (ADH). This hormone retains water in the body, diluting sodium levels. Dr. Kumar noted that this effect is more pronounced in older adults or patients taking other diuretics.

3. Carbamazepine and Oxcarbazepine
Commonly used as anti-seizure and mood-stabilizing medications, these drugs enhance ADH activity, potentially causing SIADH (Syndrome of Inappropriate Antidiuretic Hormone secretion), a well-known cause of chronic hyponatremia.

Three Commonly used Medications that can cause Hyponatremia (low blood sodium level) https://t.co/EwRh1mcfxA

— Dr Sudhir Kumar MD DM (@hyderabaddoctor) October 25, 2025

Understanding Hyponatremia
The Mayo Clinic defines hyponatremia as a condition in which the sodium concentration in the blood falls below normal levels. Sodium is a key electrolyte that regulates water balance in and around cells. When sodium is diluted, water accumulates inside cells, causing swelling that can lead to complications ranging from mild fatigue to life-threatening conditions.

Symptoms of hyponatremia include nausea, vomiting, headaches, drowsiness, confusion, muscle weakness or cramps, seizures, and in severe cases, coma. Immediate medical attention is recommended for anyone experiencing severe symptoms, such as loss of consciousness or repeated seizures.

Dr. Kumar advised that patients taking any of these medications should monitor their health closely. “If you’re on these medicines and feel unusually tired, dizzy, or confused, get your blood sodium checked,” he urged. Treatment typically focuses on addressing the underlying cause, which may include adjusting medications, restricting water intake, or administering intravenous electrolyte solutions when necessary.