Drug‑Induced Hyponatremia: What Triggers Low Sodium and How to Handle It

Ever felt dizzy, confused, or unusually tired after starting a new prescription? Those could be signs of hyponatremia—dangerously low sodium in your blood caused by certain drugs. Sodium helps keep fluid in the right places, so when it drops, your brain and muscles feel the impact. Below we break down the common culprits, the symptoms to watch for, and simple steps you can take if you suspect a problem.

Common Drugs That Can Drop Your Sodium

Not every medication affects sodium, but a handful show up again and again in doctor’s offices. Diuretics (often called water pills) like thiazides and loop diuretics push extra fluid out of your body and can also flush out sodium. Antidepressants—especially selective serotonin reuptake inhibitors (SSRIs) such as sertraline or fluoxetine—sometimes trigger the body to retain water, diluting sodium levels. Antiepileptic drugs like carbamazepine and oxcarbazepine are another group that can cause the same effect.

Even some pain relievers and anti‑nausea meds (like tramadol or ondansetron) have been linked to low sodium in vulnerable people. The risk rises if you’re older, have heart or kidney disease, or take more than one of these drugs at the same time. Knowing which pills you’re on helps you and your doctor spot trouble early.

What to Do If You Suspect Low Sodium

First, trust your body. Sudden headache, nausea, vomiting, muscle cramps, or a feeling that the room is spinning are red flags. If you notice these while you’re on a high‑risk medication, call your health‑care provider right away. They’ll likely order a simple blood test to check your sodium level.

If the test shows hyponatremia, the doctor may adjust the dose, switch you to a different drug, or add a medication that helps your kidneys keep sodium. In mild cases, simply cutting back on salty foods isn’t enough—your body needs the right balance, not just more salt. Staying hydrated with water (not sports drinks) is key, but avoid over‑drinking, which can worsen dilution.

For moderate to severe cases, treatment may involve hospital monitoring and IV fluids that carefully raise sodium without shocking the system. That’s why you shouldn’t try to self‑treat with extra salt tablets unless a doctor tells you to.

Prevention tips: ask your pharmacist or doctor if a new prescription could affect sodium, especially if you’ve had low sodium before. Regular blood‑work when you start a new medication can catch problems before symptoms appear. And keep a list of all meds—including over‑the‑counter drugs and supplements—so your provider sees the full picture.

Bottom line: drug‑induced hyponatremia isn’t rare, but it’s also manageable. Spotting the signs early, getting a quick blood test, and working with your health‑care team can keep you safe and feeling normal. If you ever feel off after a new prescription, don’t ignore it—talk to a professional and get the right checks done.