See our full Serotonin Syndrome page. It typically develops after starting or increasing a serotonergic medication, or combining two. Mild cases involve restlessness and tremor; severe cases involve high fever and muscle rigidity and are a medical emergency.
What is serotonin syndrome and how would I know if I had it?
Short answer: A potentially serious reaction from too much serotonin activity, usually from combining serotonergic medications. Watch for agitation, fever, fast heartbeat, muscle rigidity, and tremor appearing together.
Editorially reviewed
Not medical advice. This answer is general and educational. Your prescriber knows your full history and can give guidance specific to you.