Serotonin syndrome Mate taiaki aurongo
Serotonin is a chemical found in your brain. Serotonin syndrome happens when the levels of serotonin in your brain get too high.
Causes of serotonin syndrome
Many antidepressants (and some other medications) increase the amount of serotonin in your brain. Sometimes this increase can cause a reaction known as serotonin syndrome.
You are more at risk of this:
- when you first start a medication
- when you have an increase in medication dose
- if you take more than one medicine that increases serotonin
- if you take a supplement or recreational drug that can increase serotonin — supplements can include St John's wort, ginseng, L-tryptophan and 5-hydroxytryptophan (5-HTP).
Symptoms of serotonin syndrome
Serotonin syndrome is a serious reaction that can cause symptoms such as:
- headaches
- feeling sick (nausea)
- runny poos (diarrhoea)
- shaking
- muscle spasms or stiffness
- feeling restless or anxious.
Symptoms of severe serotonin syndrome include:
- a high temperature of 38°C or above
- fits (seizures)
- irregular heartbeat (arrhythmia)
- confusion or hallucinations
- loss of consciousness.
If you or someone you know experience symptoms, you should stop taking the medicine and seek advice straight away from your healthcare provider. If this is not possible, or if symptoms are severe, call 111.
Diagnosing serotonin syndrome
Your healthcare provider will diagnose you based on:
- an examination
- your symptoms
- your medication history.
There is not a single test to diagnose serotonin syndrome but they may do different tests to rule out other conditions.
Treating serotonin syndrome
Treatment for serotonin syndrome focuses on the cause and managing your symptoms. This includes stopping or reducing the dose of medications or supplements that increase your serotonin levels.
If your symptoms are mild your healthcare provider will monitor your symptoms and may use medications to control them.
If you have more severe symptoms you will need to be monitored in hospital.