Serotonin

Serotonin is one of several chemical messengers in the brain, or neurotransmitters, which help brain cells communicate with one another. Among many other functions, serotonin is involved in regulating mood. Problems with making or using the right amount of serotonin have been linked to many mental disorders, including depression, bipolar disorder, anxiety disorder, autism, and schizophrenia.

What is Serotonin?

Serotonin is an example of a neurotransmitter, a chemical messenger that is passed between nerve cells. When a nerve impulse reaches the axon at the end of a nerve, neurotransmitters are released which cross an area called the synapse to be received by a specific receptor on the end of a target nerve. Once received by the target nerve, the neurotransmitter may either excite that nerve to fire its own signal or prevent it from firing the signal.

Serotonin Biosynthesis

Serotonin Function

Serotonin and Aggression

Serotonin Pathology

The Relationship Between Serotonin and 5-HTP

Do Serotonin and Antidepressants Affect the Microbiome?

Drugs Targeting the 5-HT System

Serotonin in Plants

Latest Serotonin News and Research

Postbiotics may help treat PCOS by restoring microbiome balance

Emerging studies suggest postbiotics could aid PCOS management by restoring gut microbiome balance and enhancing insulin sensitivity and hormonal regulation.

10 Mar 2026

Modified psilocybin compounds may treat brain disorders with fewer hallucinations

Psilocybin - the psychoactive compound in "magic mushrooms" - is gaining scientific attention for its potential in treating neuropsychiatric conditions including depression, anxiety, substance use disorders and certain neurodegenerative diseases.

6 Mar 2026

Researchers propose that Parkinson’s disease may start in the gut, not the brain

A perspective in The Journal of Clinical Investigation argues that environmental exposures may interact with the gut microbiome and intestinal barrier to trigger biological processes linked to Parkinson’s disease. The authors propose that cumulative environmental stressors can erode host resilience, promoting α-synuclein pathology, immune activation, and neurodegeneration.

5 Mar 2026

Enhancing myelination may help sustain therapeutic effects of psychedelic-assisted PTSD treatment

Post-traumatic stress disorder (PTSD) is not only characterized by strongly encoded traumatic memories, but also by disrupted coordination across brain networks.

4 Mar 2026

Living in deprived neighborhoods reshapes the gut microbiome

This study reveals links between socioeconomic deprivation and gut microbiome changes, highlighting potential pathways to mental and metabolic health issues.

2 Mar 2026

Lingering brain inflammation found after mild COVID infection

Even a mild case of COVID-19 or the flu can impact the body long after the fever and cough fade, according to new Tulane University research that may help explain why some people struggle to feel fully recovered weeks or months later.

25 Feb 2026

Standard doses of antidepressants during pregnancy appear to be safe, study suggests

Using a standard dose of antidepressants during pregnancy appears to be safe for the baby, suggests new research from the University of Oslo and Akershus University Hospital.

24 Feb 2026

As more Americans embrace anxiety treatment, MAHA derides medications

After a grueling year of chemotherapy, surgery, and radiation to treat breast cancer, Sadia Zapp was anxious — not the manageable hum that had long been part of her life, but something deeper, more distracting.

23 Feb 2026

New review explores whether berries can slow cognitive decline linked to obesity

This systematic review in Nutrients evaluates human studies investigating whether polyphenol-rich berry consumption can modulate obesity-related metabolic dysfunction and support cognitive performance, particularly in individuals at risk of mild cognitive impairment. Evidence suggests modest memory benefits and possible metabolic improvements, although biomarker findings and long-term clinical relevance remain uncertain.

22 Feb 2026

Study analyzes alterations in the cerebral cortex in people with psychosis

Researchers at the University of Seville have analyzed alterations in the cerebral cortex in people suffering from psychosis.

20 Feb 2026

Short-duration psychedelic therapy shows promise for major depression treatment

A phase IIa randomized trial found that intravenous dimethyltryptamine (DMT) with structured psychological support produced rapid reductions in depressive symptoms in adults with major depressive disorder. Improvements were statistically significant versus placebo at two weeks, with mostly mild-to-moderate adverse events and the need for larger confirmatory studies emphasized.

17 Feb 2026

Synergistic drug pair shows promise for spinal cord injury recovery

Spinal cord injury remains one of the most challenging neurological conditions to treat, largely because damage continues to worsen long after the initial trauma.

16 Feb 2026

SSRI use during pregnancy linked to gestational diabetes risk and early adaptation problems in newborns

An international team of researchers has found that the use of SSRI antidepressants during pregnancy is associated with an increased risk of gestational diabetes and early adaptation problems in newborns, even after taking maternal depression into account.

13 Feb 2026

How psychedelics alter perception: A glimpse into the brain's inner world

Research findings reinforce new approaches in psychology, using psychedelic substances under medical supervision to treat certain clinical conditions.

13 Feb 2026

Adjunctive brexpiprazole boosts schizophrenia patients' information processing speed

Cognitive impairment, including decreased attention and memory, remains one of the most disabling aspects of schizophrenia, affecting social life of patients.

12 Feb 2026

Discontinuing antidepressants during pregnancy raises psychiatric risks

Pregnant patients who stopped taking their antidepressant medication during pregnancy were almost twice as likely to experience a mental health emergency compared with pregnant patients who continued taking their prescription, according to new research presented today at the Society for Maternal-Fetal Medicine (SMFM) 2026 Pregnancy Meeting.

11 Feb 2026

Review links betel nut addiction to cancer, heart disease, and metabolic risks

This review examines the epidemiology, health risks, neurobiological mechanisms, and emerging treatments related to betel nut addiction worldwide. It highlights strong links with oral cancer, cardiometabolic disease, and addiction pathways while noting limited established therapies and the need for coordinated public health strategies.

11 Feb 2026

Neural circuits in flies provide insights into human eating

Why do we sometimes keep eating even when we're full and other times turn down food completely? Why do we crave salty things at certain times, and sweets at other times? The answers, according to new neuroscience research at the University of Delaware, may lie in a tiny brain in an organism you might not expect.

30 Jan 2026

Antidepressant use does not worsen early outcomes after traumatic brain injury

Taking certain antidepressants at the time of a traumatic brain injury (TBI) is not associated with an increased risk of death, brain surgery or longer hospital stays, according to a study published on January 28, 2026, in Neurology, the medical journal of the American Academy of Neurology.

28 Jan 2026

Gut problems may shape Parkinson’s disease progression through the gut-brain axis

This narrative review examines how gastrointestinal dysfunction, gut dysbiosis, and altered gut-brain axis signaling are closely associated with the onset and progression of Parkinson’s disease. It synthesizes evidence supporting a possible bottom-up disease model while highlighting integrative, gut-targeted strategies as adjuncts to symptom management rather than proven disease-modifying therapies.

27 Jan 2026