Serotonin Syndrome: Signs, Causes, and Medications That Trigger It

When your body gets too much serotonin, a natural chemical that helps regulate mood, sleep, and digestion. Also known as serotonin toxicity, it can turn from a mild annoyance into a life-threatening emergency within hours. This isn’t just about taking too many pills—it’s about dangerous combinations that most people don’t see coming.

It usually happens when two or more drugs that boost serotonin are taken together. SSRIs, like fluoxetine or sertraline, are common culprits. But add on a migraine medicine like triptan, a painkiller like tramadol, or even an herbal supplement like St. John’s wort, and you’re stacking the odds. Even MAOIs, older antidepressants still used for treatment-resistant depression, can trigger it when mixed with newer meds. The risk isn’t theoretical—emergency rooms see this every week.

What does it feel like? You might get shaky, sweaty, or have a racing heart. Your muscles could lock up or twitch uncontrollably. Some people feel confused, agitated, or hallucinate. In severe cases, your body temperature spikes dangerously high, your blood pressure goes wild, and your organs start to fail. It’s not something you wait out. If you’re on any of these meds and suddenly feel off, get help fast.

What’s scary is how often this gets missed. Doctors might blame a bug, anxiety, or withdrawal. But if you’ve recently started a new drug, changed a dose, or added an OTC supplement, serotonin syndrome should be on the table. It’s not rare—it’s under-recognized. And the good news? If caught early, it’s treatable. Stopping the trigger drugs and getting supportive care often turns things around quickly.

Below, you’ll find real stories and facts from people who’ve been there—what meds caused it, how they spotted the signs, and how they avoided it next time. These aren’t theory pieces. They’re practical guides from patients and providers who’ve seen the fallout—and learned how to prevent it.