5-Hydroxytryptophan - PsychonautWiki


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Not to be confused with Serotonin (5-hydroxytryptamine, 5-HT).
Summary sheet: 5-Hydroxytryptophan
Chemical Nomenclature
Common names 5-HTP, Oxitriptan, Cincofarm, Levothym, Levotonine, Oxyfan, Telesol, Tript-OH, and Triptum
Substitutive name 5-Hydroxytryptophan
Systematic name 2-amino-3-(5-hydroxy-1H-indol-3-yl)propanoic acid
Class Membership
Psychoactive class Nootropic
Chemical class Tryptamine / Amino acid
Routes of Administration

WARNING: Always start with lower doses due to differences between individual body weight, tolerance, metabolism, and personal sensitivity. See responsible use section.

Threshold 25 mg
Light 50 - 100 mg
Common 100 - 300 mg
Strong 300 - 500 mg
Heavy 500 mg +

DISCLAIMER: PW's dosage information is gathered from users and resources for educational purposes only. It is not a recommendation and should be verified with other sources for accuracy.

Selective serotonin re-uptake inhibitors
Serotonin releasers
Tricyclic antidepressants

5-Hydroxytryptophan (also known as 5-HTP and oxitriptan) is a naturally occurring chemical substance and a metabolic intermediate in the biosynthesis of serotonin in the human body.[citation needed]

5-HTP is available over the counter in the United States, United Kingdom, and Canada as a dietary supplement and is sometimes used as an antidepressant, sleep aid, and appetite suppressant. It is marketed in some European countries as a prescription drug for the treatment of major depression.[1]

5-HTP is also popularly consumed by users of MDMA and other serotonin-releasing agents to try to reduce the negative after effects that begin during the substance's come down period, including anxiety, depression, and cognitive fatigue.[2] Since 5-HTP is a precursor for the neurotransmitter serotonin and MDMA administration both depletes serotonin levels in the brain as well as inhibit the enzyme needed to produce it (i.e. tryptophan hydroxylase) for a short period after,[3] it is believed that taking 5-HTP in the days after coming down will speed up the production of serotonin and decrease the time needed to recover (though there are many popular misconceptions and controversies as to just how effective it is for this purpose).[citation needed]

5-HTP should not be taken until 12 hours after one's last dose of MDMA because combining the two substances could interact to increase the brain's serotonin levels to dangerous levels, which can result in a potentially life-threatening condition called serotonin syndrome.


5-HTP or 5-Hydroxytryptophan is a synthetic indole alkaloid molecule of the tryptamine class. Tryptamines share a core structure comprised of a bicyclic indole heterocycle attached at R3 to an amino group via an ethyl side chain. 5-HTP is substituted at R5 of its indole heterocycle with a hydroxy (OH) functional group. It also contains propanoic acid group bound to the terminal amine RN of its tryptamine backbone. 5-HTP is the 5-hydroxy analog of tryptophan, and is sold in its levorotary isomer form. 5-HTP contains the core structure of serotonin with the addition of a propanoic acid at RN, and is converted by the body into serotonin by metabolic reactions.


The psychoactive action of 5-HTP is derived from its increase in production of serotonin in central nervous system tissue. 5-HTP is decarboxylated to serotonin (5-hydroxytryptamine or 5-HT) by the enzyme 'aromatic-L-amino-acid decarboxylase', with the help of vitamin B6.[4] This reaction occurs both in nervous tissue and in the liver.[5] 5-HTP crosses the blood–brain barrier, while 5-HT (serotonin) does not.[6]

Excess 5-HTP, especially when administered with vitamin B6, is thought to be metabolized and excreted.[7][8]

Subjective effects

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As such, it is still in progress and may contain incomplete or wrong information.

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Physical effects

Visual effects

Cognitive effects

Auditory effects

Experience reports

Anecdotal reports which describe the effects of this compound within our experience index include:

Additional experience reports can be found here:

Toxicity and harm potential

Due to the conversion of 5-HTP into serotonin by the liver, with prolonged use, there may be a significant risk of heart valve disease from serotonin's effect on the heart, which is thought to be due to agonism of the 5-HT2B receptors present on it.[9][10]

It has been suggested that 5-HTP may cause eosinophilia-myalgia syndrome (EMS), a serious condition which results in extreme muscle tenderness, myalgia, and blood abnormalities. However, there is evidence to show that EMS was likely caused by a contaminant in certain 5-HTP supplements instead of the substance itself.[11]

Dangerous interactions

Although many substances are safe on their own, they can become dangerous and even life-threatening when combined with other substances. The list below contains some common potentially dangerous combinations, but may not include all of them. Certain combinations may be safe in low doses of each but still increase the potential risk of death. Independent research should always be done to ensure that a combination of two or more substances is safe before consumption.

Combinations in the list below may increase the amount of neurotransmitters, such as serotonin, to dangerous or even fatal levels, resulting in life-threatening serotonin syndrome.

  • Selective serotonin re-uptake inhibitors (SSRIs) - When combined with antidepressants of the SSRI class, high doses of 5-HTP can cause acute serotonin syndrome in rats.[12][13]
  • Serotonin-norepinephrine reuptake inhibitors (SNRIs)
  • Serotonin releasers such as MDMA, 4-FA, MDAI and αMT - To prevent serotonin syndrome, 5-HTP should only be taken once the user has come down from the MDMA (or other serotonin releaser), roughly 12 hours after the last dose.
  • MAOIs such as syrian rue, banisteriopsis caapi, 2C-T-2, 2C-T-7, αMT, and some antidepressants - When combined with antidepressants of the MAOI class, high doses of 5-HTP can cause acute serotonin syndrome in rats.[12][13]
  • Tricyclic antidepressants (TCAs)
  • Tramadol

Legal status

5-HTP is commonly sold over the counter as a dietary supplement in the United States, United Kingdom, and Canada and is not subject to any illicit substance control laws.

In some parts of Europe, where it prescribed as an antidepressant, there may be some controls on its sale and distribution.[citation needed]

See also

External links


  1. https://books.google.com/books?id=5GpcTQD_L2oC&lpg=PA1528&pg=PA773&hl=en#v=onepage&q&f=false | Swiss Pharmaceutical Society (2000). Index Nominum 2000: International Drug Directory (Book with CD-ROM). Boca Raton: Medpharm Scientific Publishers. ISBN 3-88763-075-0.
  2. http://www.sciencedirect.com/science/article/pii/S0306452207006732 | Wang, X.; Baumann, M. H.; Dersch, C. M.; Rothman, R. B. (2007-08-10). "Restoration of 3,4-methylenedioxymethamphetamine-induced 5-HT depletion by the administration of l-5-hydroxytryptophan". Neuroscience. 148 (1): 212–220. doi:10.1016/j.neuroscience.2007.05.024. PMID 17629409.
  3. Acute inactivation of tryptophan hydroxylase by amphetamine analogs involves the oxidation of sulfhydryl sites | http://www.maps.org/images/pdf/1989_stone_1.pdf
  4. https://www.ncbi.nlm.nih.gov/pubmed/6983619 | Effect of pyridoxal phosphate deficiency on aromatic L-amino acid decarboxylase activity with L-DOPA and L-5-hydroxytryptophan as substrates in rats.
  5. https://www.ncbi.nlm.nih.gov/pubmed/6974228 | Characteristics of dihydroxyphenylalanine/5-hydroxytryptophan decarboxylase activity in brain and liver of cat.
  6. https://www.ncbi.nlm.nih.gov/pubmed/18445233 | Augmented brain 5-HT crosses the blood-brain barrier through the 5-HT transporter in rat.
  7. Biochemical properties and kinetic parameters of dihydroxyphenylalanine--5-hydroxytryptophan decarboxylase in brain, liver, and adrenals of cat | doi=10.1139/o79-126}}
  8. https://www.ncbi.nlm.nih.gov/pubmed/1088369 | On the tryptophan-serotonin metabolism in manic-depressive disorders. Changes in plasma 5-HT and 5-HIAA levels and urinary 5-HIAA excretion following oral loading of L-5HTP in patients with depression
  9. https://www.ncbi.nlm.nih.gov/pubmed/15781732 | Long-term serotonin administration induces heart valve disease in rats.
  10. https://www.ncbi.nlm.nih.gov/pubmed/12466135 | Serotonin mechanisms in heart valve disease II: the 5-HT2 receptor and its signaling pathway in aortic valve interstitial cells.
  11. https://www.ncbi.nlm.nih.gov/pubmed/7699627 | An eosinophilia-myalgia syndrome related disorder associated with exposure to L-5-hydroxytryptophan.
  12. 12.0 12.1 https://www.ncbi.nlm.nih.gov/pubmed/18499101 | Characterization of serotonin-toxicity syndrome (toxidrome) elicited by 5-hydroxy-l-tryptophan in clorgyline-pretreated rats.
  13. 13.0 13.1 https://www.ncbi.nlm.nih.gov/pubmed/16488409 | Effects of co-administration of a selective serotonin reuptake inhibitor and monoamine oxidase inhibitors on 5-HT-related behavior in rats.