When you take antidepressants, medications used to treat depression, anxiety, and other mood disorders. Also known as psychiatric drugs, they help balance brain chemicals—but some can quietly mess with your body’s sodium levels. This isn’t just a minor side effect. A drop in blood sodium, called hyponatremia, a condition where sodium in the blood falls below normal levels, often below 135 mmol/L, can cause confusion, seizures, even coma. It’s more common than you think, especially in older adults and people on certain types of antidepressants.
Not all antidepressants do this, but some are far more likely. SSRIs like sertraline, fluoxetine, and citalopram are the usual suspects. SNRIs like venlafaxine can also trigger it. The risk goes up if you’re over 65, take diuretics, or drink too much water. Your body holds onto water instead of flushing it out, diluting the sodium. It’s not about eating too little salt—it’s about how your body handles fluids after taking the drug. Studies show up to 1 in 10 older adults on SSRIs develop low sodium within the first few weeks. Many doctors don’t check for it unless symptoms are obvious.
What does it feel like? Mild cases might just make you feel off—headaches, nausea, tiredness. But if it gets worse, you could stumble, lose focus, or have muscle cramps. In severe cases, it can look like a stroke or dementia. That’s why it’s often missed. If you’re on an antidepressant and notice these changes, don’t wait. Get a simple blood test. Sodium levels are easy to check and fix if caught early. Stopping the drug isn’t always the answer—sometimes lowering water intake or switching meds is enough.
There’s no magic list of safe antidepressants, but some carry lower risk. Bupropion, for example, rarely causes hyponatremia. Mirtazapine and tricyclics are less likely than SSRIs. But the real key is awareness. Talk to your doctor before starting or changing meds. Ask if sodium monitoring is needed, especially if you’re older or have other health issues. This isn’t fear-mongering—it’s practical medicine. Thousands of people manage their depression without this problem, but thousands more don’t even know it’s happening.
Below, you’ll find real-world guides on how these drugs affect your body, what to watch for, and how to work with your provider to stay safe. These aren’t theory pieces—they’re based on actual patient experiences, clinical data, and medication reviews. Whether you’re taking one of these meds now or helping someone who is, the info here can make a real difference.
SSRIs can cause dangerous low sodium levels, especially in older adults, leading to confusion, falls, and even coma. Learn the risks, who’s most vulnerable, and safer alternatives like mirtazapine.
