Serotonin-Related Hyperhidrosis: Causes, Medications, and What to Do

When your body sweats too much for no clear reason—like walking into a warm room and instantly soaking through your shirt—it might not be heat or stress. It could be serotonin-related hyperhidrosis, excessive sweating triggered by medications that increase serotonin levels in the brain. Also known as drug-induced hyperhidrosis, this side effect shows up quietly but can be a warning sign of something bigger. It’s not just uncomfortable—it’s often the first clue that your nervous system is overstimulated.

This isn’t random. It happens most often with SSRIs, selective serotonin reuptake inhibitors, a common class of antidepressants, like sertraline or escitalopram. But it’s not limited to those. SNRIs, MAOIs, even some pain meds and migraine drugs can do it too. The sweating usually starts within days or weeks of starting a new drug, or after a dose increase. You might notice it under your arms, on your palms, or even while sleeping. And if you’re also feeling restless, dizzy, or your heart races? That’s not just sweat—it could be serotonin syndrome, a rare but dangerous condition caused by too much serotonin in the body. The sweating is often the earliest signal.

What makes this tricky is that doctors don’t always connect the dots. Many patients think they’re just "nervous" or "overheated." But if you’re on an antidepressant, an opioid, or even an over-the-counter cough syrup with dextromethorphan—and you’re sweating more than ever before—it’s worth asking: Could this be serotonin-related? The good news? Stopping or adjusting the medication often fixes it. But you need to act before it escalates. The posts below cover real cases, which drugs are most likely to cause this, how to tell the difference between normal sweating and a red flag, and what alternatives exist if you need to switch treatments. You’ll also find practical advice on tracking symptoms, talking to your doctor, and avoiding dangerous combinations that could push you into full serotonin syndrome.