SleepCited

Tryptophan for Insomnia

A Strong

Based on 75 studies (3 meta-analyses, 4 RCTs) with 32,701 total participants. 51/75 studies show positive effects.

Key Statistics

75

Studies

32701

Participants

↑

Positive

A Strong

Grade

Referenced Papers

Effects of L-tryptophan on sleepiness and on sleep. Review
Journal of psychiatric … None 102 citations
Compound Chaijin Jieyu Fang alleviates insomnia complicated with depression by reshaping actinobacteria to inhibit neuronal apoptosis. Other
Phytomedicine : international … 2026
Ginsenoside Rg1 alleviates PCPA-induced insomnia by inhibiting NLRP3 inflammasome activation and pyroptosis through the Nrf2/HO-1 pathway in mice. Other
Psychopharmacology 2025 5 citations
Wendan Decoction exerts therapeutic effects on insomnia by regulating gut microbiota and tryptophan metabolism. Other
Phytomedicine : international … 2025 5 citations
Lactobacillales derived from traditional Xizang dairy products improve insomnia and restore neurotransmitter-metabolic profiles via gut microbiota in PCPA-induced mice. Other
Microbiological research 2025 3 citations
Neurochemical Insights into the Role of Tryptophan Metabolites and Kynurenine Pathway in Insomnia and its Psychological and Neurological Comorbidities. Review
Molecular neurobiology 2025 3 citations
Medical Professionals and Pharmacological Intervention for the Treatment of Insomnia: A Cross-Sectional Study. Other
Sleep science (Sao … 2025 2 citations
Promotion of sleep by cinnamic acid in parachlorophenylalanine-induced insomnia in rats. Other
International immunopharmacology 2025 1 citations
Construction of composite nanoparticles of β-cyclodextrin and corn starch encapsulating 5-hydroxytryptophan for sustained release and sleep improvement in vivo. Other
International journal of … 2025 1 citations
Tryptophan metabolism-related gene CYP1B1 serves as a shared biomarker for both Parkinson's disease and insomnia. Other
Scientific reports 2025 1 citations
Characteristics and influencing factors of gut microbiota in population with sleep disorders. Other
Frontiers in microbiology 2025
[Effect of Fushen Decoction on 5-HT system and GABA expression in mouse model of PCPA-induced insomnia]. Other
Zhongguo Zhong yao … 2025
A non-pharmacological intervention for insomnia: tryptophan-fructooligosaccharides combination improves sleep in mice via anti-inflammation and gut microbiota modulation. Other
Food & function 2025
Unraveling the connection between the Mediterranean diet and sleep health: from biological mechanisms to clinical implications. Review
Sleep & breathing … 2025
[Nutrition in improving sleep quality and fighting insomnia]. Review
Nutricion hospitalaria 2025
Guhan Yangsheng Jing mitigates hippocampal neuronal pyroptotic injury and manifies learning and memory capabilities in sleep deprived mice via the … Other
Journal of ethnopharmacology 2024 26 citations
Herbal and Natural Supplements for Improving Sleep: A Literature Review. Other
Psychiatry investigation 2024 24 citations
Aspartame-induced cognitive dysfunction: Unveiling role of microglia-mediated neuroinflammation and molecular remediation. Review
International immunopharmacology 2024 21 citations
Cannabidiol Exerts Sedative and Hypnotic Effects in Normal and Insomnia Model Mice Through Activation of 5-HT1A Receptor. Other
Neurochemical research 2024 14 citations
The therapeutic potential of Ziziphi Spinosae Semen and Polygalae Radix in insomnia management: Insights from gut microbiota and serum metabolomics … Other
Journal of ethnopharmacology 2024 13 citations
Shen Yuan extract exerts a hypnotic effect via the tryptophan/5-hydroxytryptamine/melatonin pathway in mice. Other
Journal of ethnopharmacology 2024 13 citations
Study on gut microbiota and metabolomics in postmenopausal women. Other
BMC women's health 2024 12 citations
Effectiveness of Enriched Milk with Ashwagandha Extract and Tryptophan for Improving Subjective Sleep Quality in Adults with Sleep Problems: A … Other
Clocks & sleep 2024 6 citations
Biosynthetic Pathways of Tryptophan Metabolites in Saccharomyces cerevisiae Strain: Insights and Implications. Other
International journal of … 2024 5 citations
Bedtime banana and milk intake on sleep and biochemical parameters. Other
Asia Pacific journal … 2024 1 citations
Screening the effective components of Suanzaoren decoction on the treatment of chronic restraint stress induced anxiety-like mice by integrated chinmedomics … Other
Phytomedicine : international … 2023 33 citations
The Role of Supplements and Over-the-Counter Products to Improve Sleep in Children: A Systematic Review. Systematic Review
International journal of … 2023 14 citations
Development and challenges in the discovery of 5-HT1A and 5-HT7 receptor ligands. Review
Bioorganic chemistry 2023 14 citations
Structure-Based Design of Xanthine-Imidazopyridines and -Imidazothiazoles as Highly Potent and In Vivo Efficacious Tryptophan Hydroxylase Inhibitors. Other
Journal of medicinal … 2023 8 citations
Complementary and Integrative Approaches to Sleep Disorders in Children. Review
Child and adolescent … 2023 5 citations
Persistent Symptoms and IFN-γ-Mediated Pathways after COVID-19. Other
Journal of personalized … 2023 4 citations
The impact of tryptophan supplementation on sleep quality: a systematic review, meta-analysis, and meta-regression. Meta-Analysis
Nutrition reviews 2022 68 citations
Metabolic engineering of Escherichia coli for efficient production of L-5-hydroxytryptophan from glucose. Other
Microbial cell factories 2022 20 citations
Evaluation of the pharmacological effects and exploration of the mechanism of traditional Chinese medicine preparation Ciwujia tablets in treating insomnia … Other
Frontiers in pharmacology 2022 9 citations
Sleep and Diet: Mounting Evidence of a Cyclical Relationship. Other
Annual review of … 2021 149 citations
Advances in the Microbial Synthesis of 5-Hydroxytryptophan. Review
Frontiers in bioengineering … 2021 18 citations
Nutraceuticals for Sleep Disorders. Review
Combinatorial chemistry & … 2021 16 citations
[Nutrition impact on insomnia treatment]. Review
Nutricion hospitalaria 2021 3 citations
[L-tryptophan as dietetic supplement and treatment for hot flashes, astenia, and insomnia in cancer patients]. Other
Nutricion hospitalaria 2021
Enhanced production of 5-hydroxytryptophan through the regulation of L-tryptophan biosynthetic pathway. Other
Applied microbiology and … 2020 30 citations
Pharmacotherapeutic management of sleep disorders in children with neurodevelopmental disorders. Review
Expert opinion on … 2019 49 citations
Fluoxetine for adults who are overweight or obese. Review
The Cochrane database … 2019 24 citations
Study on the hypnotic effect of rare protopanaxadiol-type and protopanaxatriol-type ginsenosides. Other
RSC advances 2019 13 citations
Insomnia in Elderly Patients: Recommendations for Pharmacological Management. Review
Drugs & aging 2018 131 citations
Pilot Study of the Tart Cherry Juice for the Treatment of Insomnia and Investigation of Mechanisms. RCT
American journal of … 2018 61 citations
4-Hydroxybenzyl alcohol derivatives and their sedative-hypnotic activities. Other
RSC advances 2018 23 citations
Two combined amino acids promote sleep activity in caffeine-induced sleepless model systems. Other
Nutrition research and … 2018 12 citations
The Relationship Between Tryptophan Hydroxylase-2 Gene with Primary Insomnia and Depressive Symptoms in the Han Chinese Population. Other
Balkan medical journal 2018 10 citations
The role of tryptophan metabolism in postpartum depression. Review
Metabolic brain disease 2018
Clinical Practice Guideline for the Pharmacologic Treatment of Chronic Insomnia in Adults: An American Academy of Sleep Medicine Clinical Practice … Other
Journal of clinical … 2017 1097 citations
Tryptophan Intake in the US Adult Population Is Not Related to Liver or Kidney Function but Is Associated with Depression … Review
The Journal of … 2016 76 citations
Flos Albiziae aqueous extract and its active constituent quercetin potentiate the hypnotic effect of pentobarbital via the serotonergic system. Other
Biomedical reports 2015 12 citations
Engineering bacterial phenylalanine 4-hydroxylase for microbial synthesis of human neurotransmitter precursor 5-hydroxytryptophan. Other
ACS synthetic biology 2014 71 citations
Pharmacotherapy for sleep bruxism. Meta-Analysis
The Cochrane database … 2014 56 citations
Pharmacological evaluation of sedative and hypnotic effects of schizandrin through the modification of pentobarbital-induced sleep behaviors in mice. Other
European journal of … 2014 43 citations
Gomisin N isolated from Schisandra chinensis augments pentobarbital-induced sleep behaviors through the modification of the serotonergic and GABAergic system. Other
Fitoterapia 2014 30 citations
Gonadal hormone levels and platelet tryptophan and serotonin concentrations in perimenopausal women with or without depressive symptoms. Other
Gynecological endocrinology : … 2014 18 citations
Melatonin: comprehensive profile. Review
Profiles of drug … 2013 26 citations
Neurotransmitter-precursor-supplement intervention for detoxified heroin addicts. RCT
Journal of Huazhong … 2012 15 citations
A systematic review of insomnia and complementary medicine. Systematic Review
Sleep medicine reviews 2011 317 citations
Formulations of dietary supplements and herbal extracts for relaxation and anxiolytic action: Relarian. Review
Medical science monitor … 2009 85 citations
Both stimulatory and inhibitory effects of dietary 5-hydroxytryptophan and tyrosine are found on urinary excretion of serotonin and dopamine in … Other
Neuropsychiatric disease and … 2009 31 citations
Spinosin, a C-glycoside flavonoid from semen Zizhiphi Spinozae, potentiated pentobarbital-induced sleep via the serotonergic system. Other
Pharmacology, biochemistry, and … 2008 76 citations
Antidepressant activity of standardised extract of Marsilea minuta Linn. Other
Journal of ethnopharmacology 2008 55 citations
Oral nonprescription treatment for insomnia: an evaluation of products with limited evidence. Review
Journal of clinical … 2005
Anxiety, depression, and insomnia. Review
Primary care 2002 43 citations
Modulation of serotonergic projection from dorsal raphe nucleus to basolateral amygdala on sleep-waking cycle of rats. Other
Brain research 2002 33 citations
Melatonin and climactery. Review
Medical science monitor … 2000 11 citations
Dietary supplements and natural products as psychotherapeutic agents. Review
Psychosomatic medicine 1999 136 citations
5-Hydroxytryptophan: a clinically-effective serotonin precursor. Review
Alternative medicine review … 1998 216 citations
Fibromyalgia and the serotonin pathway. Review
Alternative medicine review … 1998
The role of 5-hydroxytryptophan (5-HTP) in the regulation of the sleep/wake cycle in parachlorophenylalanine (p-CPA) pretreated rat: a multiple approach … Other
Experimental brain research 1991 20 citations
Chronic insomnia: effects of tryptophan, flurazepam, secobarbital, and placebo. RCT
Psychopharmacology 1983 25 citations
5-HT antagonists suppress sleep and delay its restoration after 5-HTP in p-chlorophenylalanine-pretreated cats. Other
European journal of … 1982 21 citations
Effect of p-chlorophenylalanine and tryptophan on sleep, EEG and motor activity in the rat. Other
Behavioural brain research 1981 86 citations

Dosage & Usage

Commonly Used Dosages

sleep:
250-1,000 mg, before bed

Upper limit: Not established; previously recalled (1989) due to contamination

Dosages Studied in Research

Dosage Duración Effect N
1 g or more -- Positive --
Compound Chaijin Jieyu Fang (CCJF) traditional Chinese medicine formula; dose not specified -- Positive --
None -- Neutral --
not applicable (observational study) -- Neutral 165
Mixed probiotics (Lactobacillus helveticus L551, Lacticaseibacillus paracasei L578, Streptococcus th -- Positive --
5-HTP encapsulated in β-cyclodextrin/corn starch composite nanoparticles (dose not specified) -- Positive --
Cinnamic acid (CA) administered to rats (dose not specified) -- Positive --
tryptophan+FOS (TF) low dose: 10 mg/kg tryptophan + 500 mg/kg FOS; high dose: 20 mg/kg + 1000 mg/kg 2 weeks Positive --

Best taken: 30-60 minutes before bed, ideally on a light stomach

Safety & Side Effects

Reported Side Effects

  • ⚠ Nausea
  • ⚠ Diarrhea
  • ⚠ Drowsiness
  • ⚠ Dry mouth
  • ⚠ Blurred vision

Known Interactions

  • ● SSRIs/SNRIs — risk of serotonin syndrome
  • ● MAOIs — dangerous serotonin accumulation
  • ● Sedatives — additive drowsiness

Tolerable upper intake: Not established; previously recalled (1989) due to contamination

Always consult your healthcare provider before starting any supplement.

Frequently Asked Questions

Does Tryptophan help with Insomnia?
Based on 75 studies with 32,701 participants, there is strong evidence from multiple clinical trials that Tryptophan may support Insomnia management. Our evidence grade is A (Strong).
How much Tryptophan should I take for Insomnia?
Studies have used various dosages. A commonly studied range is 250-1,000 mg, before bed. Always consult your healthcare provider before starting any supplement regimen.
Are there side effects of Tryptophan?
Reported side effects may include Nausea, Diarrhea, Drowsiness, Dry mouth. Most side effects are mild and dose-dependent. Consult your doctor if you experience any adverse reactions.
How strong is the evidence for Tryptophan and Insomnia?
We rate the evidence as Grade A (Strong). This rating is based on 75 peer-reviewed studies with 32,701 total participants. The overall direction of effect is positive.

Related Evidence

Tryptophan for other conditions

Sleep Onset Difficulty B Moderate

FDA Disclaimer: These statements have not been evaluated by the Food and Drug Administration. The products and information on this website are not intended to diagnose, treat, cure, or prevent any disease. The evidence grades presented are based on our analysis of published peer-reviewed research and do not constitute medical advice. Always consult your healthcare provider before starting any supplement regimen.