Serotonin is a neurotransmitter and a hormone that helps regulate a lot of your bodily functions.Melatonincontrols the entire sleep/wake cycle, while serotonin is involved more specifically in wakefulness, triggering sleep, and REM sleep. Melatonin helps you fall asleep, while serotonin helps you wake up feeling refreshed.
Dreet Production / Getty Images
A growing pool of research suggests that people withfibromyalgia(FMS)mayhave low levels of serotonin or low serotonin activity. Experts are split, however, as to whether serotonin levels are high or low in people withchronic fatigue syndrome(CFS orME/CFS).
Some studies show that the problem in ME/CFS may lie in low serotonin-receptor activity, which could mean that the brain isn’t using serotonin properly, even if plenty is available. A newer study suggests a possible autoimmune reaction to serotonin.
Low Serotonin
No neurotransmitter acts alone. They all work together in a complex web of activity that scientists are really just beginning to understand. Still, experts have been able to associate different neurotransmitter imbalances with certain conditions and symptoms and find some ways to help boost or decrease activity.
Serotonin activity takes place in several areas of your brain, and even elsewhere around the body (where it acts as a hormone). Those different areas of your brain use serotonin differently, and they also contain several different kinds of receptors that also influence how serotonin is used.
Serotonin deficiency is associated with many physical and psychological symptoms.
Examples of physical symptoms include:
Examples of psychological symptoms include:
When serotonin levels are extremely low, additional symptoms may include:
Several disorders improve with medicines that increase the availability of serotonin, including depression, insomnia,restless leg syndrome,irritable bowel syndrome, headaches, obsessive-compulsive disorder, anorexia, bulimia, social anxiety, phobias, attention deficit disorder (ADD/ADHD), post-traumatic stress disorder, and alcoholism.
High Serotonin Levels and Serotonin Syndrome
Naturally occurring high levels of serotonin aren’t associated with many symptoms. However, taking too much of a drug that raises serotonin levels can cause a dangerous condition calledserotonin syndrome. If you suspect serotonin syndrome, you should get emergency medical help as soon as possible.
Symptoms of serotonin syndrome include:
With treatment, serotonin syndrome typically resolves within a few days. In rare cases, it can be fatal.
Increasing the Availability of Serotonin
Several prescription drugs on the market increase the amount of serotonin that’s available to your brain. In people with FMS and ME/CFS, the most common ones are selective serotonin reuptake inhibitors (SSRIs), such as Prozac (fluoxetine), Paxil (paroxetine), and Zoloft (sertraline); or serotonin-norepinephrine reuptake inhibitors (SNRIs) such as Cymbalta (duloxetine) and Savella (milnacipran), which are two of only three FDA-approved fibromyalgia treatments.
Any time you make changes to your diet or lifestyle or take new medications, be sure to make changes slowly, and track your symptoms in asymptom journalto get an accurate gauge of what may be helping. You should always work with your healthcare provider to decide what methods to try and how successful your treatments are.
8 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Al-Nimer MM, Mohammad TM, Alsakeni R.Serum levels of serotonin as a biomarker of newly diagnosed fibromyalgia in women: its relation to the platelet indices.J Res Med Sci. 2018 Aug;23(1):71. doi:10.4103/jrms.JRMS_859_17Maes M, Ringel K, Kubera M, et al.In myalgic encephalomyelitis/chronic fatigue syndrome, increased autoimmune activity against 5-HT is associated with immuno-inflammatory pathways and bacterial translocation.Journal of Affective Disorders. 2013 May;150(2):223-230. doi:10.1016/j.jad.2013.03.029Yamashita M.Potential role of neuroactive tryptophan metabolites in central fatigue: establishment of the fatigue circuit.Int J Tryptophan Res. 2020 Jun;13(1):1-12. doi:10.1177/1178646920936279Fidalgo S, Ivanov DK, Wood SH.Serotonin: from top to bottom.Biogerontology. 2012 Oct;14(1):21-45. doi:10.1007/s10522-012-9406-3Petrakis IL, Simpson TL.Posttraumatic stress disorder and alcohol use disorder: a critical review of pharmacologic treatments.Alcohol Clin Exp Res. 2017 Jan;41(2):226-237. doi:10.1111/acer.13297Uddin MF, Alweis R, Shah SR, et al.Controversies in serotonin syndrome diagnosis and management: a review.J Clin Diagn Res. 2017 Sep;11(9):5-7. doi:10.7860/JCDR/2017/29473.10696Arthritis Foundation.Medications for treating fibromyalgia symptoms.Azmitia EC.Evolution of serotonin: sunlight to suicide.Handbook of Behavioral Neuroscience. 2020 Jan;31(1):3-22. doi:10.1016/B978-0-444-64125-0.00001-3Additional ReadingGoldstein J.The pathophysiology of chronic fatigue syndrome and related neurosomatic disorders.Journal of Chronic Fatigue Syndrome. 2000;6(2):83-91. doi:10.1300/j092v06n02_09Smith AK, Dimulescu I, Falkenberg VR, et al.Genetic evaluation of the serotonergic system in chronic fatigue syndrome.Psychoneuroendocrinology. 2008;33(2):188-97. doi:10.1016/j.psyneuen.2007.11.001Yamada T, Terashima T, Kawano S, et al.Theanine, gamma-glutamylethylamide, a unique amino acid in tea leaves, modulates neurotransmitter concentrations in the brain striatum interstitium in conscious rats.Amino Acids. 2009;36(1):21-7. doi:10.1007/s00726-007-0020-7
8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Al-Nimer MM, Mohammad TM, Alsakeni R.Serum levels of serotonin as a biomarker of newly diagnosed fibromyalgia in women: its relation to the platelet indices.J Res Med Sci. 2018 Aug;23(1):71. doi:10.4103/jrms.JRMS_859_17Maes M, Ringel K, Kubera M, et al.In myalgic encephalomyelitis/chronic fatigue syndrome, increased autoimmune activity against 5-HT is associated with immuno-inflammatory pathways and bacterial translocation.Journal of Affective Disorders. 2013 May;150(2):223-230. doi:10.1016/j.jad.2013.03.029Yamashita M.Potential role of neuroactive tryptophan metabolites in central fatigue: establishment of the fatigue circuit.Int J Tryptophan Res. 2020 Jun;13(1):1-12. doi:10.1177/1178646920936279Fidalgo S, Ivanov DK, Wood SH.Serotonin: from top to bottom.Biogerontology. 2012 Oct;14(1):21-45. doi:10.1007/s10522-012-9406-3Petrakis IL, Simpson TL.Posttraumatic stress disorder and alcohol use disorder: a critical review of pharmacologic treatments.Alcohol Clin Exp Res. 2017 Jan;41(2):226-237. doi:10.1111/acer.13297Uddin MF, Alweis R, Shah SR, et al.Controversies in serotonin syndrome diagnosis and management: a review.J Clin Diagn Res. 2017 Sep;11(9):5-7. doi:10.7860/JCDR/2017/29473.10696Arthritis Foundation.Medications for treating fibromyalgia symptoms.Azmitia EC.Evolution of serotonin: sunlight to suicide.Handbook of Behavioral Neuroscience. 2020 Jan;31(1):3-22. doi:10.1016/B978-0-444-64125-0.00001-3Additional ReadingGoldstein J.The pathophysiology of chronic fatigue syndrome and related neurosomatic disorders.Journal of Chronic Fatigue Syndrome. 2000;6(2):83-91. doi:10.1300/j092v06n02_09Smith AK, Dimulescu I, Falkenberg VR, et al.Genetic evaluation of the serotonergic system in chronic fatigue syndrome.Psychoneuroendocrinology. 2008;33(2):188-97. doi:10.1016/j.psyneuen.2007.11.001Yamada T, Terashima T, Kawano S, et al.Theanine, gamma-glutamylethylamide, a unique amino acid in tea leaves, modulates neurotransmitter concentrations in the brain striatum interstitium in conscious rats.Amino Acids. 2009;36(1):21-7. doi:10.1007/s00726-007-0020-7
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Al-Nimer MM, Mohammad TM, Alsakeni R.Serum levels of serotonin as a biomarker of newly diagnosed fibromyalgia in women: its relation to the platelet indices.J Res Med Sci. 2018 Aug;23(1):71. doi:10.4103/jrms.JRMS_859_17Maes M, Ringel K, Kubera M, et al.In myalgic encephalomyelitis/chronic fatigue syndrome, increased autoimmune activity against 5-HT is associated with immuno-inflammatory pathways and bacterial translocation.Journal of Affective Disorders. 2013 May;150(2):223-230. doi:10.1016/j.jad.2013.03.029Yamashita M.Potential role of neuroactive tryptophan metabolites in central fatigue: establishment of the fatigue circuit.Int J Tryptophan Res. 2020 Jun;13(1):1-12. doi:10.1177/1178646920936279Fidalgo S, Ivanov DK, Wood SH.Serotonin: from top to bottom.Biogerontology. 2012 Oct;14(1):21-45. doi:10.1007/s10522-012-9406-3Petrakis IL, Simpson TL.Posttraumatic stress disorder and alcohol use disorder: a critical review of pharmacologic treatments.Alcohol Clin Exp Res. 2017 Jan;41(2):226-237. doi:10.1111/acer.13297Uddin MF, Alweis R, Shah SR, et al.Controversies in serotonin syndrome diagnosis and management: a review.J Clin Diagn Res. 2017 Sep;11(9):5-7. doi:10.7860/JCDR/2017/29473.10696Arthritis Foundation.Medications for treating fibromyalgia symptoms.Azmitia EC.Evolution of serotonin: sunlight to suicide.Handbook of Behavioral Neuroscience. 2020 Jan;31(1):3-22. doi:10.1016/B978-0-444-64125-0.00001-3
Al-Nimer MM, Mohammad TM, Alsakeni R.Serum levels of serotonin as a biomarker of newly diagnosed fibromyalgia in women: its relation to the platelet indices.J Res Med Sci. 2018 Aug;23(1):71. doi:10.4103/jrms.JRMS_859_17
Maes M, Ringel K, Kubera M, et al.In myalgic encephalomyelitis/chronic fatigue syndrome, increased autoimmune activity against 5-HT is associated with immuno-inflammatory pathways and bacterial translocation.Journal of Affective Disorders. 2013 May;150(2):223-230. doi:10.1016/j.jad.2013.03.029
Yamashita M.Potential role of neuroactive tryptophan metabolites in central fatigue: establishment of the fatigue circuit.Int J Tryptophan Res. 2020 Jun;13(1):1-12. doi:10.1177/1178646920936279
Fidalgo S, Ivanov DK, Wood SH.Serotonin: from top to bottom.Biogerontology. 2012 Oct;14(1):21-45. doi:10.1007/s10522-012-9406-3
Petrakis IL, Simpson TL.Posttraumatic stress disorder and alcohol use disorder: a critical review of pharmacologic treatments.Alcohol Clin Exp Res. 2017 Jan;41(2):226-237. doi:10.1111/acer.13297
Uddin MF, Alweis R, Shah SR, et al.Controversies in serotonin syndrome diagnosis and management: a review.J Clin Diagn Res. 2017 Sep;11(9):5-7. doi:10.7860/JCDR/2017/29473.10696
Arthritis Foundation.Medications for treating fibromyalgia symptoms.
Azmitia EC.Evolution of serotonin: sunlight to suicide.Handbook of Behavioral Neuroscience. 2020 Jan;31(1):3-22. doi:10.1016/B978-0-444-64125-0.00001-3
Goldstein J.The pathophysiology of chronic fatigue syndrome and related neurosomatic disorders.Journal of Chronic Fatigue Syndrome. 2000;6(2):83-91. doi:10.1300/j092v06n02_09Smith AK, Dimulescu I, Falkenberg VR, et al.Genetic evaluation of the serotonergic system in chronic fatigue syndrome.Psychoneuroendocrinology. 2008;33(2):188-97. doi:10.1016/j.psyneuen.2007.11.001Yamada T, Terashima T, Kawano S, et al.Theanine, gamma-glutamylethylamide, a unique amino acid in tea leaves, modulates neurotransmitter concentrations in the brain striatum interstitium in conscious rats.Amino Acids. 2009;36(1):21-7. doi:10.1007/s00726-007-0020-7
Goldstein J.The pathophysiology of chronic fatigue syndrome and related neurosomatic disorders.Journal of Chronic Fatigue Syndrome. 2000;6(2):83-91. doi:10.1300/j092v06n02_09
Smith AK, Dimulescu I, Falkenberg VR, et al.Genetic evaluation of the serotonergic system in chronic fatigue syndrome.Psychoneuroendocrinology. 2008;33(2):188-97. doi:10.1016/j.psyneuen.2007.11.001
Yamada T, Terashima T, Kawano S, et al.Theanine, gamma-glutamylethylamide, a unique amino acid in tea leaves, modulates neurotransmitter concentrations in the brain striatum interstitium in conscious rats.Amino Acids. 2009;36(1):21-7. doi:10.1007/s00726-007-0020-7
Meet Our Medical Expert Board
Share Feedback
Was this page helpful?Thanks for your feedback!What is your feedback?OtherHelpfulReport an ErrorSubmit
Was this page helpful?
Thanks for your feedback!
What is your feedback?OtherHelpfulReport an ErrorSubmit
What is your feedback?
