Apollo neurologist warns these three common medicines can cause dangerously low sodium levels

Some commonly prescribed medicines — including antidepressants and blood pressure drugs — can cause dangerously low sodium levels, warns Apollo doctor (Image: Pexels)

Most people think good health means eating less salt, but having too little sodium can be dangerous, too. When blood sodium drops below normal levels, it messes up the body's fluid and electrolyte balance. Doctors call this hyponatremia.

Dr Sudhir Kumar, who works as a senior neurologist at Apollo Hospitals in Hyderabad, recently posted a video on X. He warned about the hidden risks of low sodium caused by some common medications.

He advised patients taking these drugs to stay alert for signs such as weakness, confusion, dizziness, fatigue, or seizures.

Also Read: High blood pressure, stroke, heart disease risk: India’s salt habit needs a reset, says ICMR study

“If you’re on any of these medicines and begin to feel unusually weak, dizzy, or mentally foggy, it’s important to have your sodium levels checked,” said Dr Kumar.

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

1. Thiazide Diuretics

Commonly prescribed for high blood pressure and water retention, drugs like hydrochlorothiazide and indapamide help the body flush out excess salt and fluids. However, in some people, they can reduce sodium to dangerously low levels. You might notice feeling tired, getting muscle cramps, or having trouble focusing at first. If you don't treat it, these symptoms can get worse and lead to confusion or even seizures.

Advice: Hydrate and drink ample amount of water and frequently check your sodium levels and kidney functioning from your doctor.

2. Antidepressants (SSRIs)

Drugs like sertraline, fluoxetine, and escitalopram that are used to treat depression or anxiety can also throw off the body's sodium balance. These medicines might trigger a hormone that causes the body to hold onto water, which thins out the sodium in the blood. People who are older or taking several medications face a higher risk.

Advice: If you notice you're feeling sleepy or confused while on antidepressants, get in touch with your doctor right away.

3. Anti-Seizure and Mood-Stabilising Drugs

Drugs like carbamazepine and oxcarbazepine that are used for stabilising mood or controlling seizures can cause a condition known as SIADH (Syndrome of Inappropriate Antidiuretic Hormone secretion), where the body retains excess water. Water retention can in turn, lower sodium levels, sometimes without any clear symptoms.

Advice: It is crucial to do regular blood tests and closely monitor health, especially for those people who have pre-existing heart or kidney issues.

Why Sodium Is Important

Maintaining proper levels of sodium is key to maintaining proper fluid balance, nerve function, and muscle activity. When levels reduce or fall too low, cells — especially in the brain — begin to swell, leading to headaches, confusion, seizures, or even coma in severe cases.

Also Read: 7 reasons why high-sodium diet is bad for your health

Even though hyponatremia often develops quietly, it can become serious when linked to medication use. Never stop or alter your prescribed drugs without medical advice. Instead, stay informed, monitor your health, and discuss any unusual symptoms promptly.

As Dr Kumar concludes, “Awareness and timely testing are essential to prevent complications.”

FAQs on Medications Linked with Low Sodium Levels

Q: What medications can cause low sodium levels?

Thiazide diuretics, antidepressants (SSRIs), and anti-seizure and mood-stabilising drugs can cause low sodium levels.

Q: What symptoms should I watch out for if I am on these medications?

Symptoms include weakness, confusion, dizziness, fatigue, or seizures.

Q: What should I do if I experience these symptoms?

Contact your doctor immediately and get your sodium levels checked.

Q: How can I prevent low sodium levels while on these medications?

Stay hydrated, monitor your sodium levels and kidney function regularly, and consult with your doctor.

Q: Are older people at a higher risk of low sodium levels from these medications?

Yes, older individuals and those taking multiple medications are at a higher risk.

Disclaimer: This article, including health and fitness advice, only provides generic information. Don’t treat it as a substitute for qualified medical opinion. Always consult a specialist for specific health diagnosis.