Serotonin sends signals between nerve cells. It may help regulate many body functions, including mood, bowel movements, and sleep. Some medications help boost serotonin levels and improve mood.
Serotonin is both a neurotransmitter and a hormone. This chemical is produced by nerve cells and sends signals between them.
Serotonin is found in many parts of the body, including the digestive system, blood platelets, and the central nervous system. It’s also thought to regulate mood.
Serotonin is made from the essential amino acid tryptophan. This amino acid enters the body through the food you eat and is commonly found in meat, dairy products, eggs, and nuts.
Serotonin affects every part of you — from your emotions to your motor skills. It helps with sleeping, healing, and digesting. Serotonin is also thought to be a natural mood stabilizer.
Serotonin helps your body to:
- balance your mood and experience pleasure
- heal wounds
- clot blood
- control movement
More specifically, serotonin intervenes in these functions:
- Bowel movements:
About 90% of the serotonin in your body is produced in your intestines. It helps control bowel movements and function. - Mood: Serotonin in the brain is believed to regulate feelings, including happiness and anxiety. Selective serotonin reuptake inhibitors (SSRIs) are thought to help treat mood disorders by increasing serotonin activity in your brain.
- Nausea: Serotonin in your stomach and intestines helps your body feel nausea and start vomiting in response to illness, foods, or other conditions.
- Sleep and waking: Neurotransmitters, including serotonin, regulate your ability to stay awake. While you sleep, serotonin is involved in switching between REM and non-REM sleep.
- Blood clotting: Platelets in your blood store serotonin. When your body needs to repair damage, platelets release serotonin to help stop bleeding and heal wounds.
- Sex drive: Serotonin is involved in controlling the body’s sexual functions. This may be why medications that affect serotonin levels are associated with sexual side effects.
Serotonin and mental health
Some medications used to manage mental health conditions work by changing how your brain uses serotonin.
Early theories suggested that chronic low serotonin is the main cause of depression. However,
Mood disorders like depression may be caused by a combination of factors, including brain changes, life experiences, and health conditions.
Even so, antidepressant medications continue to be an important first-line treatment for mood disorders, along with psychotherapy.
Serotonin vs. dopamine
Like serotonin, dopamine is a chemical communicator found in the brain and many other parts of the body.
Both of these neurotransmitters are associated with your mental well-being, so it can be easy to confuse them. But there are also some key differences between the two.
Here are several ways that serotonin and dopamine may act differently in your body:
| Serotonin | Dopamine | |
|---|---|---|
| Where it’s produced | mainly in your gut | mainly in your brain |
| Mood | stabilizes mood and anxiety | affects motivation and pleasure |
| Depression | targeted in common depression treatments | few depression treatments target it |
| Sleep | helps regulate sleep and wakefulness | helps you feel more alert |
Only a healthcare professional can determine if you need to boost your serotonin levels. High levels of serotonin may lead to toxicity and unwanted side effects, so it’s important to take your medications following a doctor’s recommendations.
Medication, as well as natural options, can increase serotonin levels.
SSRIs
SSRIs are the most commonly prescribed type of antidepressant medication. They increase serotonin levels in the brain by blocking the reabsorption of serotonin, so more of it remains active.
There are several SSRIs, including fluoxetine (Prozac) and sertraline (Zoloft).
When you’re taking medications that affect serotonin, you’ll want to speak with a doctor before using other medications or supplements. Mixing medications may put you at risk of a serious condition called serotonin syndrome.
Supplements
Some supplements may have the ability to raise serotonin levels. However, they’re not a replacement for medications prescribed by a doctor and should not be taken alongside medications that affect your serotonin levels.
Supplements that may affect serotonin include:
- St. John’s wort: The herb St. John’s wort increases serotonin in the body. Some believe it is effective for treating depression, but this
has not always been supported by research. - SAMe: This supplement is
promoted as a treatment for depression, but more research is needed to understand its effects on mood and serotonin levels. - Tryptophan: This substance can be converted into serotonin in your brain, potentially raising your serotonin levels. Some
research suggests it could help improve mood and reduce anxiety.
All of these supplements can increase your risk for serotonin syndrome, as well as cause other side effects and interactions.
Speak with a healthcare professional before trying any new supplements or herbal remedies, especially if you’re taking prescription drugs.
Natural serotonin boosters
The following strategies may help you balance your serotonin levels and improve your mood:
- Exposure to bright light: Bright sunlight may help your mood, which is why light therapy is commonly recommended for treating seasonal depression. SAD lamps are an option for home therapy in winter or when access to bright sunlight is difficult.
- Exercise: Regular exercise has many benefits for overall health. It can have mood-boosting effects and may trigger the release of serotonin.
- Health-promoting diet: Following a balanced diet lowers the risk of many health conditions. Although research is limited, eating foods that may promote serotonin production could positively affect mood.
- Meditation: Meditating can help relieve stress and promote a positive outlook on life.
Medications, supplements, and other substances that increase serotonin levels in your body can lead to serotonin syndrome.
Serotonin syndrome can happen when you:
- start taking a new medication that boosts serotonin levels
- increase the dosage of an existing medication
- take more medication than the amount prescribed
- use an additional medication, supplement, or drug that also affects serotonin levels
Medications, supplements, and substances that affect serotonin levels include:
- SSRIs
- monoamine oxidase inhibitors (MAOIs)
- dextromethorphan
- many medications prescribed for mental health conditions
- St. John’s wort
- SAMe
- tryptophan
- amphetamines
- cocaine
- MDMA (ecstasy)
The symptoms of serotonin syndrome include:
- tremors
- sweating
- nausea
- vomiting
- restlessness
- anxiety
Severe symptoms can include:
- headache
- flushed skin
- dilated pupils
- disorientation
- increased reflexes (hyperreflexia)
- muscle twitches or spasms
- high fever
- muscle stiffness
- rapid heart rate
- high blood pressure
- irregular heartbeat
To diagnose serotonin syndrome, a doctor will perform a detailed history and physical exam.
Tests are not required for a diagnosis but may be requested to assess the severity of the symptoms and determine the treatment plan. These may include:
- brain imaging
- urine tests
- blood tests
- spinal tap (lumbar puncture)
In mild cases, a medical professional may ask you to stop taking the serotonin medication so that your symptoms can resolve. In more severe cases, they may use additional medications to treat the symptoms and reduce the risk of complications.
Hospital treatment is typically necessary to manage severe serotonin syndrome. Usually, symptoms resolve within
If you suspect serotonin syndrome, it’s important to get medical attention immediately. Serotonin syndrome can be life threatening if left untreated.
What does serotonin do to a person?
Your body naturally produces serotonin, although its levels may vary depending on many factors. Serotonin affects your mood, sleep cycle, digestion, sex drive, and blood clotting, among many other things.
Low levels of serotonin may lead to low mood (depression), and some people may need to take medications to boost their levels. Only a healthcare professional can determine if and when this is the case.
Is anxiety a sign of too much serotonin?
Anxiety and irritability can be symptoms of an increase in serotonin levels. Higher levels of serotonin may be a temporary reaction to starting some depression medications or combining different serotonin-boosting drugs.
Anxiety, in general, is not a sign of too much serotonin in people who don’t take these medications.
Does serotonin make you happy?
Serotonin is known as a “feel-good hormone.” It’s associated with mood regulation and the ability to experience pleasure.
If your serotonin levels are persistently low, you may see an improvement in your mood once you start taking serotonin-boosting medications. Only a healthcare professional can determine if you may benefit from this type of treatment.
Serotonin affects every part of your body, including mood regulation, blood clotting, and digestion.
Sometimes, a serotonin imbalance can mean something more serious. It’s important to pay attention to your body and talk with a doctor about any concerns.