Low Sodium from Antidepressants: What You Need to Know

When you take antidepressants, medications used to treat depression, anxiety, and other mood disorders, most people focus on how they affect mood, sleep, or energy. But there’s a quieter, less talked-about side effect that can be dangerous: low sodium, a condition called hyponatremia where blood sodium levels drop too low. It’s not common, but it happens often enough—especially in older adults, women, and people on certain types of antidepressants like SSRIs and SNRIs. If your body’s sodium gets too diluted, you can feel dizzy, nauseous, confused, or even have seizures. This isn’t just a lab number—it’s a real health risk.

How does this happen? Some antidepressants interfere with a hormone called ADH, which controls how your kidneys hold onto water. When ADH gets overactive, your body keeps too much water, which dilutes the sodium in your blood. It’s not because you’re eating too little salt—it’s because your body’s water balance is off. Hyponatremia, the medical term for low sodium in the blood shows up most often in people over 65, those taking higher doses, or those already on diuretics or other meds that affect fluid levels. It’s also more likely if you drink a lot of water while on these drugs, thinking it’s healthy. The truth? Too much water with certain antidepressants can push sodium down fast.

You won’t always feel it at first. Mild cases might just make you feel a little off—headaches, tiredness, or trouble concentrating. But if it gets worse, it can mimic a stroke or cause falls, confusion, or even coma. The good news? Most cases are caught early with a simple blood test. If your doctor knows you’re on an antidepressant and you’re feeling strange, they’ll check your sodium levels. Stopping the drug isn’t always needed—sometimes just cutting back on water or switching to another antidepressant fixes it. But ignoring it? That’s when things get serious.

This is why it’s important to talk to your doctor—not just about how you’re feeling emotionally, but physically too. Are you bloated? Do you feel unusually tired? Have you been drinking more water than usual? These aren’t just random symptoms. They could be signs your sodium is dropping. And while not everyone on antidepressants gets this, it’s something you should know about, especially if you’re older or taking more than one medication. The posts below cover real cases, warning signs, and what to do if you’re worried. You’ll find info on which antidepressants carry the highest risk, how labs track this issue, and what alternatives exist if sodium balance becomes a problem. This isn’t about fear—it’s about being informed so you can take control of your health without stopping the meds you need.