Serotonin Syndrome: What You Need to Know About This Rare Medication Risk

Serotonin—often called the body's "feel good" chemical—is crucial for mood, sleep, digestion, and more. But when it comes to serotonin, it's possible to have too much of a good thing.

Serotonin syndrome is a rare but potentially serious condition that occurs when you have excess serotonin in your body. At Next Step Psychiatry in Lilburn, GA, we believe patients should understand the medications they take—including potential risks and how to stay safe.

What Does Serotonin Do?

Serotonin is a neurotransmitter that carries signals throughout your body. At normal levels, it helps you feel focused, emotionally stable, happy, and calm. Serotonin also plays important roles in:

• Digestion: Controls bowel function and regulates appetite
• Sleep: Helps regulate your sleep-wake cycle (your body uses serotonin to make melatonin)
• Wound healing: Helps wounds stop bleeding and heal faster
• Nausea: Triggers nausea and vomiting when your body needs to expel something harmful
• Mood: Low serotonin is associated with depression, which is why many antidepressants target serotonin levels

What Is Serotonin Syndrome?

Serotonin syndrome occurs when you have dangerously high serotonin levels in your body. This typically happens when you take more than one medication (or supplement) that increases serotonin at the same time.

Important context: Most medications that affect serotonin are completely safe when taken as prescribed. Serious cases of serotonin syndrome are rare, and most cases are mild enough that people don't seek medical care. However, severe cases can be life-threatening, which is why awareness matters.

Symptoms of Serotonin Syndrome

Symptoms usually appear within 24 hours of taking a new medication or increasing a dose—sometimes within just an hour.

Mild Symptoms

• Nervousness
• Nausea and vomiting
• Diarrhea
• Dilated pupils
• Tremor

Moderate Symptoms

• Agitation and restlessness
• Muscle twitching or spasms
• Muscle rigidity
• Sweating and shivering
• Abnormal eye movements

Severe Symptoms (Seek Emergency Care)

• Confusion or delirium
• Rapid heart rate
• High blood pressure
• High body temperature
• Seizures
• Passing out

What Causes Serotonin Syndrome?

Serotonin syndrome most commonly occurs when people take two or more medications that affect serotonin simultaneously. It can also happen from:

• Taking too much of a serotonin-affecting medication
• Increasing the dose of certain antidepressants
• Combining medications with certain supplements
• Using illicit drugs that increase serotonin

Medications That Affect Serotonin

Antidepressants

• SSRIs: Prozac, Zoloft, Lexapro, Paxil, Celexa
• SNRIs: Effexor, Cymbalta, Pristiq
• Tricyclic antidepressants: Amitriptyline, nortriptyline
• MAOIs: Marplan, Nardil

Other Medications

• Pain medications (fentanyl, tramadol, meperidine)
• Cough medications containing dextromethorphan
• Migraine medications (triptans)
• Anti-nausea medications (Zofran, Reglan)
• Lithium (mood stabilizer)

Supplements and Substances

• St. John's Wort
• Ginseng
• 5-HTP and tryptophan
• MDMA (ecstasy), LSD, cocaine, amphetamines

Treatment

Treatment depends on severity:

• Mild cases: Stopping the medication or decreasing the dosage usually resolves symptoms within 24-72 hours
• Moderate cases: May require observation in the hospital
• Severe cases: Require ICU admission for close monitoring and supportive care

Never stop your medication suddenly without your psychiatrist's guidance. If you're experiencing concerning symptoms, contact your doctor or seek emergency care.

How to Prevent Serotonin Syndrome

• Keep a complete medication list: Include all prescriptions, over-the-counter drugs, and supplements
• Share your medication list with all providers: Your psychiatrist, primary care doctor, and any specialists should know everything you take
• Ask about interactions: Before starting any new medication or supplement, ask your doctor about potential interactions
• Pay attention to symptoms: When starting a new medication, watch for unusual symptoms and report them promptly
• Follow dosing instructions: Take medications exactly as prescribed

The Bottom Line

Serotonin syndrome is rare, and antidepressants are safe when taken as prescribed. By being informed about what you take and communicating openly with your healthcare providers, you can minimize your risk while getting the mental health treatment you need.