5-Hydroxytryptophan

Not to be confused with serotonin (5-hydroxytryptamine, 5-HT).

5-Hydroxytryptophan


IUPAC name 2-amino-3- (5-hydroxy-1H-indol-3-yl) propanoic acid
Identifiers
CAS number	56-69-9^Y
PubChem	144
ChemSpider	388413^Y
UNII	C1LJO185Q9^Y
KEGG	D07339^Y
MeSH	5-Hydroxytryptophan
ChEBI	CHEBI:17780^Y
ChEMBL	CHEMBL350221^Y
Jmol-3D images	Image 1
SMILES O=C(O)[C@@H](N)Cc2c1cc(O)ccc1nc2
InChI InChI=1S/C11H12N2O3/c12-9(11(15)16)3-6-5-13-10-2-1-7(14)4-8(6)10/h1-2,4-5,9,13-14H,3,12H2,(H,15,16)/t9-/m0/s1^Y Key: LDCYZAJDBXYCGN-VIFPVBQESA-N^Y InChI=1/C11H12N2O3/c12-9(11(15)16)3-6-5-13-10-2-1-7(14)4-8(6)10/h1-2,4-5,9,13-14H,3,12H2,(H,15,16)/t9-/m0/s1 Key: LDCYZAJDBXYCGN-VIFPVBQEBZ
Properties
Molecular formula	C₁₁H₁₂N₂O₃
Molar mass	220.23 g/mol
Y (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

5-Hydroxytryptophan (5-HTP), also known as oxitriptan (INN), is a naturally occurring amino acid and chemical precursor as well as metabolic intermediate in the biosynthesis of the neurotransmitters serotonin and melatonin from tryptophan.

5-HTP is sold over-the-counter in the United Kingdom, United States and Canada as a dietary supplement for use as an antidepressant, appetite suppressant, and sleep aid, and is also marketed in many European countries for the indication of major depression under trade names like Cincofarm, Levothym, Levotonine, Oxyfan, Telesol, Tript-OH, and Triptum.^[1]^[2] Several double-blind placebo-controlled clinical trials have demonstrated the effectiveness of 5-HTP in the treatment of depression,^[1] though a lack of high quality studies has been noted.^[3]

1 Metabolism
2 Pharmacology
3 Dietary sources
4 Therapeutic use
5 Possible risks or side effects
6 See also
7 References
8 Further reading

Metabolism

5-Hydroxytryptophan 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,^[6] while 5-HT does not. Excess 5-HTP, especially when administered with Vitamin B6, is thought to be metabolized and excreted.^[7]^[8]

5-HTP	AAAD	Serotonin

	PLP

Pharmacology

The psychoactive action of 5-HTP is derived from its effect on the production of serotonin in central nervous system tissue. More specifically, 5-HTP increases the production of serotonin.^[9] Thus, it has been used to treat conditions such as depression, for which the lack of serotonin is thought to be a contributing factor.^[10]

Research shows that co-administration with carbidopa greatly increases plasma 5-HTP levels.^[11] However, several studies have reported that 5-HTP is effective even without a peripheral decarboxylase inhibitor (e.g. carbidopa).^[12] Other studies have indicated the risk of a scleroderma-like condition resulting from the combination of 5-HTP and carbidopa.^[13]

Dietary sources

Though 5-HTP is found in food only in insignificant quantities, it is a chemical involved intermediately in the metabolism of tryptophan, an amino acid found in turkey, milk, potatoes, pumpkin, and various greens.^[14] See also the section Dietary sources of the article on L-tryptophan.

Therapeutic use

5-HTP is sold over-the-counter in the United States, the United Kingdom, and Canada as a dietary supplement for use as an antidepressant, appetite suppressant, and sleep aid. 5-HTP in supplement form is typically sold in 50 mg or 100 mg gelatin or vegetarian capsules. It is usually sourced from the seeds of Griffonia simplicifolia.

5-HTP has been studied and shown to be of benefit in the following conditions: primary fibromyalgia syndrome,^[15] Friedreich's ataxia,^[16] depression, anxiety, binge eating associated with obesity, and insomnia.^[17] There is no statistically significant difference between 5-HTP and placebo in treating chronic headaches (primary or otherwise).^[18]

A 2001 meta-analysis found that of 108 studies on 5-HTP published between 1966 and 2000, only two met the authors' quality standards for inclusion. The two studies that were deemed of sufficient quality did not deal with 5-HTP exclusively, instead combining results for 5-HTP and tryptophan, so the results may not be completely applicable for 5-HTP alone. While the combined analysis of the two 5-HTP and tryptophan studies showed significant effectiveness over placebo in treating depression, the authors state that overall "the evidence was of insufficient quality to be conclusive". They also state that "because alternative antidepressants exist which have been proven to be effective and safe, the clinical usefulness of 5-HTP and tryptophan is limited at present".^[3]

Possible risks or side effects

Because 5-HTP has not been thoroughly studied in a clinical setting, possible side effects and interactions with other drugs are not well known.

Administered serotonin has been shown to increase the risk of heart valve disease in animals.^[19]^[20] 5-HTP has not been subjected to this test. Oral 5-HTP results in an increase in urinary 5-HIAA, a serotonin metabolite, indicating that 5-HTP is peripherally metabolized to serotonin, which is then metabolized. This might cause a false positive test in tests looking for carcinoid syndrome.^[21]

5-HTP can cause hypertension by increasing plasma renin activity, when not co-administered with a peripheral aromatic L-amino acid decarboxylase inhibitor, such as carbidopa or benserazide.^[22]

Direct and indirect evidence for possible yet unproven risks and side effects associated with 5-HTP when overdosed:

Heart valve damage or disease (cardiac fibrosis).^[19]^[20]
When combined with MAOIs or SSRIs, 5-HTP can cause acute serotonin syndrome.^[23]^[24]
When combined with carbidopa (as a treatment for symptoms of Parkinson's disease), 5-HTP causes nausea and vomiting; however this can be alleviated via administration of granisetron.^[25] As mentioned above under pharmacology, cases of scleroderma-like illness have been reported in patients using carbidopa and 5-HTP.^[26]

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 caused by a contaminant in early 5-HTP supplements, before the introduction of the current Good Manufacturing Practices by the United States FDA in 2007. Many countries now employ similar regulation..^[27]

References

^ ^a ^b Turner EH, Blackwell AD (2005). "5-Hydroxytryptophan plus SSRIs for interferon-induced depression: synergistic mechanisms for normalizing synaptic serotonin". Medical Hypotheses 65 (1): 138–44. doi:10.1016/j.mehy.2005.01.026. PMID 15893130. http://linkinghub.elsevier.com/retrieve/pii/S0306-9877(05)00068-X.
^ Swiss Pharmaceutical Society (2000). Index Nominum 2000: International Drug Directory (Book with CD-ROM). Boca Raton: Medpharm Scientific Publishers. ISBN 3-88763-075-0. http://books.google.com/?id=5GpcTQD_L2oC&lpg=PA1528&pg=PA773#v=onepage.
^ ^a ^b Shaw K, Turner J, Del Mar C (2002). Shaw, Kelly A. ed. "Tryptophan and 5-hydroxytryptophan for depression". Cochrane Database of Systematic Reviews (Online) (1): CD003198. doi:10.1002/14651858.CD003198. PMID 11869656.
^ Rahman MK, Nagatsu T, Sakurai T, Hori S, Abe M, Matsuda M (1982). "Effect of pyridoxal phosphate deficiency on aromatic L-amino acid decarboxylase activity with L-DOPA and L-5-hydroxytryptophan as substrates in rats". Jpn. J. Pharmacol. 32 (5): 803–11. doi:10.1254/jjp.32.803. PMID 6983619.
^ Bouchard, S; Bousquet, C; Roberge, AG (1981). "Characteristics of dihydroxyphenylalanine/5-hydroxytryptophan decarboxylase activity in brain and liver of cat". Journal of neurochemistry 37 (3): 781–7. PMID 6974228.
^ Gomes P, Soares-da-Silva P. (1999). "L-DOPA transport properties in an immortalised cell line of rat capillary cerebral endothelial cells, RBE 4". Brain Res. 829 (1–2): 143–150. doi:10.1016/S0006-8993(99)01387-6. PMID 18445233.
^ Bouchard S, Roberge AG (1979). "Biochemical properties and kinetic parameters of dihydroxyphenylalanine--5-hydroxytryptophan decarboxylase in brain, liver, and adrenals of cat". Can. J. Biochem. 57 (7): 1014–8. doi:10.1139/o79-126. PMID 39668.
^ Amamoto T, Sarai K (1976). "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". Hiroshima J. Med. Sci. 25 (2–3): 135–40. PMID 1088369.
^ "5-HTP: Uses, Side Effects, Interactions and Warnings - WebMD". http://www.webmd.com/vitamins-supplements/ingredientmono-794-5-HTP.aspx?activeIngredientId=794&activeIngredientName=5-HTP. Retrieved 2009-10-05.
^ "Health.com: 5-hydroxytryptophan : Information on Uses, Dosage & Side Effects on Health.com". http://tools.health.com/natstandardcontent/5-htp-1#H7. Retrieved 2009-10-05.
^ Magnussen I, Jensen TS, Rand JH, Van Woert MH (1981). "Plasma accumulation of metabolism of orally administered single dose L-5-hydroxytryptophan in man". Acta pharmacologica et toxicologica 49 (3): 184–9. doi:10.1111/j.1600-0773.1981.tb00890.x. PMID 6175178.
^ Birdsall TC (1998). "5-Hydroxytryptophan: a clinically-effective serotonin precursor". Alternative medicine review : a journal of clinical therapeutic 3 (4): 271–80. PMID 9727088.
^ Sternberg EM, Van Woert MH, Young SN, et al. (1980). "Development of a scleroderma-like illness during therapy with L-5-hydroxytryptophan and carbidopa". N. Engl. J. Med. 303 (14): 782–7. doi:10.1056/NEJM198010023031403. PMID 6997735.
^ "5-Hydroxytryptophan". University of Maryland Medical Center. http://www.umm.edu/altmed/articles/5-hydroxytryptophan-000283.htm. Retrieved 2010-01-21.
^ Caruso I, Sarzi Puttini P, Cazzola M, Azzolini V (1990). "Double-blind study of 5-hydroxytryptophan versus placebo in the treatment of primary fibromyalgia syndrome". The Journal of International Medical Research 18 (3): 201–9. PMID 2193835.
^ Trouillas P, Serratrice G, Laplane D, et al. (May 1995). "Levorotatory form of 5-hydroxytryptophan in Friedreich's ataxia. Results of a double-blind drug-placebo cooperative study". Archives of Neurology 52 (5): 456–60. PMID 7733839. http://archneur.ama-assn.org/cgi/pmidlookup?view=long&pmid=7733839. Retrieved 2009-07-30.
^ Birdsall TC (August 1998). "5-Hydroxytryptophan: a clinically-effective serotonin precursor". Alternative Medicine Review : a Journal of Clinical Therapeutic 3 (4): 271–80. PMID 9727088. http://www.thorne.com/altmedrev/.fulltext/3/4/271.pdf. Retrieved 2009-07-30.
^ De Benedittis G, Massei R (1985). "Serotonin precursors in chronic primary headache. A double-blind cross-over study with L-5-hydroxytryptophan vs. placebo". Journal of Neurosurgical Sciences 29 (3): 239–48. PMID 3913752.
^ ^a ^b Gustafsson BI, Tømmerås K, Nordrum I, Loennechen JP, Brunsvik A, Solligård E, Fossmark R, Bakke I, Syversen U, Waldum H (March 2005). "Long-term serotonin administration induces heart valve disease in rats". Circulation 111 (12): 1517–22. doi:10.1161/01.CIR.0000159356.42064.48. PMID 15781732.
^ ^a ^b Xu J, Jian B, Chu R, Lu Z, Li Q, Dunlop J, Rosenzweig-Lipson S, McGonigle P, Levy RJ, Liang B (December 2002). "Serotonin Mechanisms in Heart Valve Disease II : The 5-HT2 Receptor and Its Signaling Pathway in Aortic Valve Interstitial Cells". Am. J. Pathol. 161 (6): 2209–18. doi:10.1016/S0002-9440(10)64497-5. PMC 1850896. PMID 12466135. http://ajp.amjpathol.org/cgi/content/abstract/161/6/2209.
^ Joy T, Walsh G, Tokmakejian S, Van Uum SH (January 2008). "Increase of urinary 5-hydroxyindoleacetic acid excretion but not serum chromogranin A following over-the-counter 5-hydroxytryptophan intake". Can. J. Gastroenterol. 22 (1): 49–53. PMC 2659120. PMID 18209781. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2659120.
^ Barney CC, Threatte RM, Kikta DC, Fregly MJ. (June 1981). "Effects of serotonin and L-5-hydroxytryptophan on plasma renin activity in rats". Pharmacol Biochem Behav. 14 (6): 895–900. doi:10.1016/0091-3057(81)90380-4. PMID 7019933.
^ Ma Z, Zhang G, Jenney C, Krishnamoorthy S, Tao R. (July 2008). "Characterization of serotonin-toxicity syndrome (toxidrome) elicited by 5-hydroxy-l-tryptophan in clorgyline-pretreated rats". Eur J Pharmacol. 588 (2–3): 198–206. doi:10.1016/j.ejphar.2008.04.004. PMID 18499101.
^ Izumi T, Iwamoto N, Kitaichi Y, Kato A, Inoue T, Koyama T. (2006). "Effects of co-administration of a selective serotonin reuptake inhibitor and monoamine oxidase inhibitors on 5-HT-related behavior in rats". Eur J Pharmacol. 532 (3): 258–264. doi:10.1016/j.ejphar.2005.12.075. PMID 16488409.
^ Jacobs G, Kamerling I, de Kam M, et al. (Nov 2008). "Enhanced tolerability of the 5-hydroxytryptophane challenge test combined with granisetron". J Psychopharmacol. (Oxford) 24 (1): 65–72. doi:10.1177/0269881108094299. PMID 18719048.
^ http://www.truestarhealth.com/Notes/1339004.html
^ Michelson, D; Page, SW, Casey, R, Trucksess, MW, Love, LA, Milstien, S, Wilson, C, Massaquoi, SG, Crofford, LJ, Hallett, M (1994 Dec). "An eosinophilia-myalgia syndrome related disorder associated with exposure to L-5-hydroxytryptophan". The Journal of rheumatology 21 (12): 2261–5. PMID 7699627.

den Boer JA, Westenberg HG (1990). "Behavioral, neuroendocrine, and biochemical effects of 5-hydroxytryptophan administration in panic disorder". Psychiatry research 31 (3): 267–78. doi:10.1016/0165-1781(90)90096-N. PMID 2139731.
Angst J, Woggon B, Schoepf J (1977). "The treatment of depression with L-5-hydroxytryptophan versus imipramine. Results of two open and one double-blind study". Archiv für Psychiatrie und Nervenkrankheiten 224 (2): 175–86. PMID 336002.
article at Psychology Today
Turner EH, Loftis JM, Blackwell AD (2006). "Serotonin a la carte: supplementation with the serotonin precursor 5-hydroxytryptophan". Pharmacol. Ther. 109 (3): 325–38. doi:10.1016/j.pharmthera.2005.06.004. PMID 16023217.
5-Hydroxytryptophan (5-HTP) Supplement Information at University of Maryland Medical Center

Antidepressants (N06A)

Specific reuptake inhibitors (RIs), enhancers (REs), and releasing agents (RAs)

Selective serotonin reuptake inhibitors (SSRIs)	Alaproclate • Citalopram • Escitalopram • Femoxetine • Fluoxetine^# • Fluvoxamine • Indalpine • Ifoxetine • Litoxetine • Lubazodone • Panuramine • Paroxetine • Pirandamine • Seproxetine • Sertraline^# • Zimelidine^‡

Serotonin–norepinephrine reuptake inhibitors (SNRIs)	Bicifadine • Clovoxamine • Desvenlafaxine • Duloxetine • Levomilnacipran • Eclanamine • Milnacipran • Sibutramine • Venlafaxine

Serotonin–norepinephrine–dopamine reuptake inhibitors (SNDRIs)	Brasofensine • BTS-74,398 • Cocaine • Diclofensine • DOV-21,947 • DOV-102,677 • DOV-216,303 • EXP-561 • Fezolamine • JNJ-7925476 • NS-2359 • PRC200-SS • Pridefine • SEP-225,289 • SEP-227,162 • Tesofensine

Norepinephrine reuptake inhibitors (NRIs)	Amedalin • Atomoxetine/Tomoxetine • Binedaline • Ciclazindol • Daledalin • Esreboxetine • Lortalamine • Mazindol • Nisoxetine • Reboxetine • Talopram • Talsupram • Tandamine • Viloxazine

Dopamine reuptake inhibitors (DRIs)	Medifoxamine • Vanoxerine

Norepinephrine-dopamine reuptake inhibitors (NDRIs)	Amineptine • Bupropion/Amfebutamone^# • Cilobamine • Manifaxine • Methylphenidate • Nomifensine • Radafaxine • Tametraline

Norepinephrine-dopamine releasing agents (NDRAs)	Amphetamine • Befuraline • Lisdexamfetamine • Methamphetamine • Phenethylamine • Piberaline • Tranylcypromine

Serotonin-norepinephrine-dopamine releasing agents (SNDRAs)	4-Methyl-αMT • αET/Etryptamine • αMT/Metryptamine

Selective serotonin reuptake enhancers (SSREs)	Tianeptine

Others	Indeloxazine • Teniloxazine • Tramadol • Viqualine

Receptor antagonists and/or reuptake inhibitors

Serotonin antagonists and reuptake inhibitors (SARIs)	Etoperidone • Nefazodone • Trazodone

Noradrenergic and specific serotonergic antidepressants (NaSSAs)	Aptazapine • Esmirtazapine • Mianserin • Mirtazapine • Setiptiline/Teciptiline

Norepinephrine-dopamine disinhibitors (NDDIs)	Agomelatine

Serotonin modulators and stimulators (SMSs)	Vortioxetine

Others	Tedatioxetine • Vilazodone

Heterocyclic antidepressants (bi-, tri-, and tetracyclics)

Bicyclics	Tiazesim

Tricyclics	Amezepine • Amineptine • Amitriptyline^# • Amitriptylinoxide • Azepindole • Butriptyline • Cianopramine • Clomipramine • Cotriptyline • Cyanodothiepin • Demexiptiline • Depramine/Balipramine • Desipramine • Dibenzepin • Dimetacrine • Dosulepin/Dothiepin • Doxepin • Enprazepine • Fluotracen • Hepzidine • Homopipramol • Imipramine • Imipraminoxide • Intriptyline • Iprindole • Ketipramine • Litracen • Lofepramine • Losindole • Mariptiline • Melitracen • Metapramine • Mezepine • Naranol • Nitroxazepine • Nortriptyline • Noxiptiline • Octriptyline • Opipramol • Pipofezine • Propizepine • Protriptyline • Quinupramine • Tampramine • Tianeptine • Tienopramine • Trimipramine;

Tetracyclics	Amoxapine • Aptazapine • Azipramine • Ciclazindol • Ciclopramine • Esmirtazapine • Maprotiline • Mazindol • Mianserin • Mirtazapine • Oxaprotiline • Setiptiline/Teciptiline

Monoamine oxidase inhibitors (MAOIs)

Nonselective	Irreversible: Benmoxin • Echinopsidine • Iproclozide • Iproniazid • Isocarboxazid • Mebanazine • Metfendrazine • Nialamide • Octamoxin • Phenelzine • Pheniprazine • Phenoxypropazine • Pivalylbenzhydrazine • Safrazine • Tranylcypromine; Reversible: Caroxazone • Paraxazone;• Quercetin;

MAO_A-Selective	Irreversible: Clorgiline; Reversible: Amiflamine • Bazinaprine • Befloxatone • Befol • Berberine • Brofaromine • Cimoxatone • Esuprone • Harmala Alkaloids (Harmine, Harmaline, Tetrahydroharmine, Harman, Norharman, etc) • Methylene Blue • Metralindole • Minaprine • Moclobemide • Pirlindole • Sercloremine • Tetrindole • Toloxatone • Tyrima;

MAO_B-Selective	Irreversible: Ladostigil • Mofegiline • Pargyline • Rasagiline • Selegiline; Reversible: Lazabemide • Milacemide

Azapirones and other 5-HT_1A receptor agonists

Alnespirone • Aripiprazole • Befiradol • Buspirone • Eptapirone • Flesinoxan • Flibanserin • Gepirone • Ipsapirone • Oxaflozane • Tandospirone • Vilazodone • Zalospirone

^#WHO-EM. ^‡Withdrawn from market. Clinical trials: ^†Phase III. ^§Never to phase III

M: PSO/PSI

mepr

dsrd (o, p, m, p, a, d, s), sysi/epon, spvo

proc(eval/thrp), drug(N5A/5B/5C/6A/6B/6D)

Anxiolytics (N05B)

GABA_A PAMs

Benzodiazepine	Adinazolam • Alprazolam • Bretazenil • Bromazepam • Camazepam • Chlordiazepoxide • Clobazam • Clonazepam • Clorazepate • Clotiazepam • Cloxazolam • Diazepam • Ethyl Loflazepate • Etizolam • Fludiazepam • Halazepam • Imidazenil • Ketazolam • Lorazepam • Medazepam • Nordazepam • Oxazepam • Pinazepam • Prazepam

Carbamates	Emylcamate • Mebutamate • Meprobamate (Carisoprodol, Tybamate) • Phenprobamate • Procymate

Nonbenzodiazepines	Abecarnil • Adipiplon • Alpidem • CGS-8216 • CGS-9896 • CGS-13767 • CGS-20625 • Divaplon • ELB-139 • Fasiplon • GBLD-345 • Gedocarnil • L-838,417 • NS-2664 • NS-2710 • Ocinaplon • Pagoclone • Panadiplon • Pipequaline • RWJ-51204 • SB-205,384 • SL-651,498 • Taniplon • TP-003 • TP-13 • TPA-023 • Y-23684 • ZK-93423

Pyrazolopyridines	Cartazolate • Etazolate • ICI-190,622 • Tracazolate

Others	Chlormezanone • Ethanol (Alcohol) • Etifoxine • Kavalactones (Kava Kava) • Skullcap • Valerenic Acid (Valerian)

α₂δ VDCC Blockers

Gabapentin • Pregabalin

5-HT_1A Agonists

Azapirones: Buspirone • Gepirone • Tandospirone; Others: Flesinoxan • Oxaflozane

H₁ Antagonists

Diphenylmethanes: Captodiame • Hydroxyzine; Others: Brompheniramine • Chlorpheniramine • Pheniramine

CRH₁ Antagonists

Antalarmin • CP-154,526 • Pexacerfont • Pivagabine

NK₂ Antagonists

GR-159,897 • Saredutant

MCH₁ antagonists

ATC-0175 • SNAP-94847

mGluR₂_/₃ Agonists

DAA-1097 • DAA-1106 • Emapunil • FGIN-127 • FGIN-143

σ₁ agonists

Afobazole • Opipramol

Others

Benzoctamine • Carbetocin • Demoxytocin • Mephenoxalone • Mepiprazole • Oxanamide • Oxytocin • Promoxolane • Tofisopam • Trimetozine • WAY-267,464

^#WHO-EM. ^‡Withdrawn from market. Clinical trials: ^†Phase III. ^§Never to phase III

M: PSO/PSI

mepr

dsrd (o, p, m, p, a, d, s), sysi/epon, spvo

proc(eval/thrp), drug(N5A/5B/5C/6A/6B/6D)

Antiobesity agents/Anorectics (A08)

Central

Stimulants	4-Methylamphetamine • Amfecloral • Amfepentorex • Amfepramone • Aminorex • Amphetamine • Amphetaminil • Atomoxetine • Benfluorex^‡ • Benzphetamine • Bupropion • Cathine • Cathinone • Chlorphentermine • Ciclazindol • Clobenzorex • Cloforex • Clominorex • Clortermine • Dexfenfluramine • Dextroamphetamine • Dextromethamphetamine • Dexmethylphenidate • Difemetorex • Dimethylcathinone • Diphemethoxidine • Ephedrine • Ephedra • Ethylamphetamine • Etolorex • Fenbutrazate • Fencamfamine • Fenethylline • Fenfluramine (+phentermine) • Fenproporex • Fludorex • Fluminorex • Furfenorex • Indanorex • Khat • Levopropylhexedrine • Lisdexamfetamine • Manifaxine • Mazindol • Mefenorex • Methamphetamine • Methylphenidate • Norfenfluramine • Pemoline • Pentorex (Phenpentermine) • Phendimetrazine • Phenethylamine • Phenmetrazine • Phentermine • Phenylpropanolamine • Pipradrol • Prolintane • Propylhexedrine • Pseudoephedrine • Pyrovalerone • Radafaxine • Reboxetine • Setazindol • Sibutramine • Synephrine • Tesofensine • Viloxazine • Xylopropamine • Zylofuramine

Cannabinoids	Ibipinabant • Otenabant • Rimonabant • Surinabant • Taranabant

Others	5-HTP • Galactomannan (Guar Gum) • Glucomannan • L-DOPA • L-Phenylalanine • L-Tryptophan • L-Tyrosine • Lorcaserin • Lu AA-33810 • Metformin • Naltrexone • Naloxone • Oxyntomodulin • P57 • Peptide YY • Topiramate • Yohimbine (Yohimbe) • Zonisamide

Peripheral

Cetilistat • Dinitrophenol^‡ • Oleoyl-Estrone • Orlistat • Simmondsin • Sterculia

^#WHO-EM. ^‡Withdrawn from market. Clinical trials: ^†Phase III. ^§Never to phase III

M: NUT

cof, enz, met

noco, nuvi, sysi/epon, met

drug(A8/11/12)

Hypnotics/Sedatives (N05C)

GABA_A Agonists/PAMs	Barbiturates: Allobarbital • Amobarbital • Aprobarbital • Barbital • Butabarbital • Butobarbital • Cyclobarbital • Ethallobarbital • Heptabarb • Hexobarbital • Mephobarbital • Methohexital • Pentobarbital • Phenobarbital • Proxibarbal • Reposal • Secobarbital • Talbutal • Thiamylal • Thiopental • Vinbarbital • Vinylbital Benzodiazepines: Brotizolam • Clonazepam • Cinolazepam • Climazolam • Doxefazepam • Estazolam • Flunitrazepam • Flurazepam • Flutoprazepam • Haloxazolam • Loprazolam • Lorazepam •Lormetazepam • Midazolam • Nimetazepam • Nitrazepam • Quazepam • Temazepam • Triazolam Carbamates: Carisoprodol • Ethinamate • Hexapropymate • Meprobamate • Methocarbamol • Procymate • Tybamate Neuroactive Steroids: Acebrochol • Allopregnanolone • Alphadolone • Alphaxolone • Eltanolone • Ganaxolone • Hydroxydione • Minaxolone • Org 20599 • Org 21465 • Tetrahydrodeoxycorticosterone Nonbenzodiazepines: CL-218,872 • Eszopiclone • Indiplon • JM-1232 • Lirequinil • Necopidem • Pazinaclone • ROD-188 • Saripidem • Suproclone • Suriclone • SX-3228 • U-89843A • U-90042 • Zaleplon • Zolpidem • Zopiclone Phenols: Fospropofol • Propofol Piperidinediones: Glutethimide • Methyprylon • Pyrithyldione • Piperidione Quinazolinones: Afloqualone • Cloroqualone • Diproqualone • Etaqualone • Mebroqualone • Mecloqualone • Methaqualone • Methylmethaqualone • Nitromethaqualone Volatiles/gases: 2-Methyl-2-butanol • Acetophenone • Acetylglycinamide chloral hydrate • Centalun • Chloral hydrate • Ethanol (Alcohol) • Paraldehyde • Trichloroethanol Others: Bromide (Lithium bromide, Potassium bromide, Sodium bromide) • Chloralose • Chloralodol • Clomethiazole • Dichloralphenazone • Ethchlorvynol • Etomidate • Gaboxadol • Loreclezole • Methylpentynol • Metomidate • Org 25435 • Petrichloral • Sulfonmethane • Triclofos • Valerenic acid (Valerian)

GABA_B Agonists	1,4-Butanediol • Aceburic acid • GABOB • GHB (Sodium oxybate) • GBL • GVL

H₁ Inverse agonists	Antihistamines: Captodiame • Cyproheptadine • Diphenhydramine • Doxylamine • Hydroxyzine • Methapyrilene • Pheniramine • Promethazine • Propiomazine Antidepressants: Tricyclic antidepressants (Amitriptyline, Doxepin, Trimipramine, etc.) • Tetracyclic antidepressants (Mianserin, Mirtazapine, etc.) Antipsychotics: Typical antipsychotics (Chlorpromazine, Thioridazine, etc.) • Atypical antipsychotics (Olanzapine, Quetiapine, Risperidone, etc.)

α₁-Adrenergic Antagonists	Antidepressants: Serotonin antagonists and reuptake inhibitors (Trazodone) • Tricyclic antidepressants (Amitriptyline, Doxepin, Trimipramine, etc.) • Tetracyclic antidepressants (Mianserin) Antipsychotics: Typical antipsychotics (Chlorpromazine, Thioridazine, etc.) • Atypical antipsychotics (Olanzapine, Quetiapine, Risperidone, etc.) Others: Niaprazine

α₂-Adrenergic Agonists	4-NEMD • Clonidine • Detomidine • Dexmedetomidine • Lofexidine • Medetomidine • Romifidine • Tizanidine • Xylazine

5-HT_2A Antagonists	Antidepressants: Serotonin antagonists and reuptake inhibitors (Trazodone) • Tricyclic antidepressants (Amitriptyline, Doxepin, Trimipramine, etc.) • Tetracyclic antidepressants (Mianserin, Mirtazapine, etc.) Antipsychotics: Typical antipsychotics (Chlorpromazine, Thioridazine, etc.) • Atypical antipsychotics (Olanzapine, Quetiapine, Risperidone, etc.) Others: Eplivanserin • Niaprazine • Pruvanserin • Volinanserin

Melatonin Agonists	Agomelatine • LY-156,735 • Melatonin • Ramelteon • Tasimelteon

Orexin Antagonists	Almorexant • SB-334,867 • SB-408,124 • SB-649,868 • Suvorexant • TCS-OX2-29

Others	Acecarbromal • Apronal • Bromisoval • Cannabidiol (Cannabis) • Carbromal • Embutramide • Evoxine • Fenadiazole • Gabapentin • Kavalactones (Kava) • Mephenoxalone • Opioids (Oxycodone, Morphine (Opium), etc.) • Passion flower • Scopolamine (Mandrake) • Valnoctamide

Neurotransmitter metabolic intermediates

catecholamines

Anabolism (tyrosine→epinephrine)	Tyrosine → Levodopa → Dopamine → Norepinephrine → Epinephrine

Catabolism/ metabolites	dopamine: DOPAL · DOPAC · MOPET · Hydroxytyrosol · 3-Methoxytyramine · Homovanillic acid norepinephrine: 3,4-Dihydroxymandelic acid · Normetanephrine · Vanillylmandelic acid · 3-Methoxy-4-hydroxyphenylglycol · Dihydroxyphenylethylene glycol epinephrine: Metanephrine

tryptophan→serotonin

anabolism: 5-Hydroxytryptophan
catabolism: 5-Hydroxyindoleacetic acid

serotonin→melatonin

Normelatonin

M: MET

mt, k, c/g/r/p/y/i, f/h/s/l/o/e, a/u, n, m

k, cgrp/y/i, f/h/s/l/o/e, au, n, m, epon

m(A16/C10),i(k, c/g/r/p/y/i, f/h/s/o/e, a/u, n, m)

Serotonergics

5-HT₁ receptor ligands

5-HT_1A	Agonists: Azapirones: Alnespirone • Binospirone • Buspirone • Enilospirone • Eptapirone • Gepirone • Ipsapirone • Perospirone • Revospirone • Tandospirone • Tiospirone • Umespirone • Zalospirone; Antidepressants: Etoperidone • Nefazodone • Trazodone • Vortioxetine; Antipsychotics: Aripiprazole • Asenapine • Clozapine • Quetiapine • Ziprasidone; Ergolines: Dihydroergotamine • Ergotamine • Lisuride • Methysergide • LSD; Tryptamines: 5-CT • 5-MeO-DMT • 5-MT • Bufotenin • DMT • Indorenate • Psilocin • Psilocybin; Others: 8-OH-DPAT • Adatanserin • Bay R 1531 • Befiradol • BMY-14802 • Cannabidiol • Dimemebfe • Ebalzotan • Eltoprazine • F-11,461 • F-12,826 • F-13,714 • F-14,679 • F-15,063 • F-15,599 • Flesinoxan • Flibanserin • Lesopitron • LY-293,284 • LY-301,317 • MKC-242 • NBUMP • Osemozotan • Oxaflozane • Pardoprunox • Piclozotan • Rauwolscine • Repinotan • Roxindole • RU-24,969 • S 14,506 • S-14,671 • S-15,535 • Sarizotan • SSR-181,507 • Sunepitron • U-92,016-A • Urapidil • Vilazodone • Xaliproden • Yohimbine Antagonists: Antipsychotics: Iloperidone • Risperidone • Sertindole; Beta blockers: Alprenolol • Cyanopindolol • Iodocyanopindolol • Oxprenolol • Pindobind • Pindolol • Propranolol • Tertatolol; Others: AV965 • BMY-7,378 • CSP-2503 • Dotarizine • Flopropione • GR-46611 • Isamoltane • Lecozotan • Mefway • Metitepine/Methiothepin • MPPF • NAN-190 • PRX-00023 • Robalzotan • S-15535 • SB-649,915 • SDZ 216-525 • Spiperone • Spiramide • Spiroxatrine • UH-301 • WAY-100,135 • WAY-100,635 • Xylamidine

5-HT_1B	Agonists: Lysergamides: Dihydroergotamine • Ergotamine • Methysergide; Piperazines: Eltoprazine • TFMPP; Triptans: Avitriptan • Eletriptan • Sumatriptan • Zolmitriptan; Tryptamines: 5-CT • 5-MT; Others: CGS-12066A • CP-93,129 • CP-94,253 • CP-135,807 • RU-24,969 • Vortioxetine Antagonists: Lysergamides: Metergoline; Others: AR-A000002 • Elzasonan • GR-127,935 • Isamoltane • Metitepine/Methiothepin • SB-216,641 • SB-224,289 • SB-236,057 • Yohimbine

5-HT_1D	Agonists: Lysergamides: Dihydroergotamine • Methysergide; Triptans: Almotriptan • Avitriptan • Eletriptan • Frovatriptan • Naratriptan • Rizatriptan • Sumatriptan • Zolmitriptan; Tryptamines: 5-CT • 5-Ethyl-DMT • 5-MT • 5-(Nonyloxy)tryptamine; Others: CP-135,807 • CP-286,601 • GR-46611 • L-694,247 • L-772,405 • PNU-109,291 • PNU-142,633 Antagonists: Lysergamides: Metergoline; Others: Alniditan • BRL-15,572 • Elzasonan • GR-127,935 • Ketanserin • LY-310,762 • LY-367,642 • LY-456,219 • LY-456,220 • Metitepine/Methiothepin • Ritanserin • Yohimbine • Ziprasidone

5-HT_1E	Agonists: Lysergamides: Methysergide; Triptans: Eletriptan; Tryptamines: BRL-54443 • Tryptamine Antagonists: Metitepine/Methiothepin

5-HT_1F	Agonists: Triptans: Eletriptan • Naratriptan • Sumatriptan; Tryptamines: 5-MT; Others: BRL-54443 • Lasmiditan • LY-334,370 Antagonists: Metitepine/Methiothepin

5-HT₂ receptor ligands


5-HT_2A	Agonists: Lysergamides: ALD-52 • Ergometrine • Lisuride • LA-SS-Az • LSD • LSD-Pip • Lysergic acid 2-butyl amide • Lysergic acid 3-pentyl amide • Methysergide; Phenethylamines: 25I-NBF • 25I-NBMD • 25I-NBOH • 25I-NBOMe • 2C-B • 2C-B-FLY • 2CB-Ind • 2C-C-NBOMe • 2C-E • 2C-I • 2C-TFM-NBOMe • 2C-T-2 • 2C-T-7 • 2C-T-21 • 2CBCB-NBOMe • 2CBFly-NBOMe • Bromo-DragonFLY • DOB • DOC • DOI • DOM • MDA • MDMA • Mescaline • TCB-2 • TFMFly; Piperazines: BZP • Quipazine • TFMPP; Tryptamines: 5-CT • 5-MeO-α-ET • 5-MeO-α-MT • 5-MeO-DET • 5-MeO-DiPT • 5-MeO-DMT • 5-MeO-DPT • 5-MT • α-ET • α-Methyl-5-HT • α-MT • Bufotenin • DET • DiPT • DMT • DPT • Psilocin • Psilocybin; Others: AL-34662 • AL-37350A • Dimemebfe • Medifoxamine • Oxaflozane • PNU-22394 • RH-34 Antagonists: Atypical antipsychotics: Amperozide • Aripiprazole • Carpipramine • Clocapramine • Clorotepine • Clozapine • Gevotroline • Iloperidone • Melperone • Mosapramine • Olanzapine • Paliperidone • Pimozide • Quetiapine • Risperidone • Sertindole • Ziprasidone • Zotepine; Typical antipsychotics: Loxapine • Pipamperone; Antidepressants: Amitriptyline • Amoxapine • Aptazapine • Etoperidone • Mianserin • Mirtazapine • Nefazodone • Teniloxazine • Trazodone; Others: 5-I-R91150 • 5-MeO-NBpBrT • AC-90179 • Adatanserin • Altanserin • AMDA • APD-215 • Blonanserin • Cinanserin • CSP-2503 • Cyproheptadine • Deramciclane • Dotarizine • Eplivanserin • Esmirtazapine • Fananserin • Flibanserin • Ketanserin • KML-010 • Lubazodone • Mepiprazole • Metitepine/Methiothepin • Nantenine • Pimavanserin • Pizotifen • Pruvanserin • Rauwolscine • Ritanserin • S-14,671 • Sarpogrelate • Setoperone • Spiperone • Spiramide • SR-46349B • Volinanserin • Xylamidine • Yohimbine

5-HT_2B	Agonists: Oxazolines: 4-Methylaminorex • Aminorex; Phenethylamines: Chlorphentermine • Cloforex • DOB • DOC • DOI • DOM • Fenfluramine • MDA • MDMA • Norfenfluramine; Tryptamines: 5-CT • 5-MT • α-Methyl-5-HT; Others: BW-723C86 • Cabergoline • mCPP • Pergolide • PNU-22394 • Ro60-0175 Antagonists: Agomelatine • Asenapine • EGIS-7625 • Ketanserin • Lisuride • LY-272,015 • Metitepine/Methiothepin • PRX-08066 • Rauwolscine • Ritanserin • RS-127,445 • Sarpogrelate • SB-200,646 • SB-204,741 • SB-206,553 • SB-215,505 • SB-221,284 • SB-228,357 • SDZ SER-082 • Tegaserod • Yohimbine

5-HT_2C	Agonists: Phenethylamines: 2C-B • 2C-E • 2C-I • 2C-T-2 • 2C-T-7 • 2C-T-21 • DOB • DOC • DOI • DOM • MDA • MDMA • Mescaline; Piperazines: Aripiprazole • mCPP • TFMPP; Tryptamines: 5-CT • 5-MeO-α-ET • 5-MeO-α-MT • 5-MeO-DET • 5-MeO-DiPT • 5-MeO-DMT • 5-MeO-DPT • 5-MT • α-ET • α-Methyl-5-HT • α-MT • Bufotenin • DET • DiPT • DMT • DPT • Psilocin • Psilocybin; Others: A-372,159 • AL-38022A • CP-809,101 • Dimemebfe • Lorcaserin• Medifoxamine • MK-212 • Org 12,962 • ORG-37,684 • Oxaflozane • PNU-22394 • Ro60-0175 • Ro60-0213 • Vabicaserin • WAY-629 • WAY-161,503 • YM-348 Antagonists: Atypical antipsychotics: Clorotepine • Clozapine • Iloperidone • Melperone • Olanzapine • Paliperidone • Pimozide • Quetiapine • Risperidone • Sertindole • Ziprasidone • Zotepine; Typical antipsychotics: Chlorpromazine • Loxapine • Pipamperone; Antidepressants: Agomelatine • Amitriptyline • Amoxapine • Aptazapine • Etoperidone • Fluoxetine • Mianserin • Mirtazapine • Nefazodone • Nortriptyline • Tedatioxetine • Trazodone; Others: Adatanserin • Cinanserin • Cyproheptadine • Deramciclane • Dotarizine • Eltoprazine • Esmirtazapine • FR-260,010 • Ketanserin • Ketotifen • Latrepirdine • Metitepine/Methiothepin • Methysergide • Pizotifen • Ritanserin • RS-102,221 • S-14,671 • SB-200,646 • SB-206,553 • SB-221,284 • SB-228,357 • SB-242,084 • SB-243,213 • SDZ SER-082 • Xylamidine

5-HT₃, 5-HT₄, 5-HT₅, 5-HT₆, 5-HT₇ ligands


5-HT₃	Agonists: Piperazines: BZP • Quipazine; Tryptamines: 2-Methyl-5-HT • 5-CT; Others: Chlorophenylbiguanide • Butanol • Ethanol • Halothane • Isoflurane • RS-56812 • SR-57,227 • SR-57,227-A • Toluene • Trichloroethane • Trichloroethanol • Trichloroethylene • YM-31636 Antagonists: Antiemetics: AS-8112 • Alosetron • Azasetron • Batanopride • Bemesetron • Cilansetron • Dazopride • Dolasetron • Granisetron • Lerisetron • Ondansetron • Palonosetron • Ramosetron • Renzapride • Tropisetron • Zacopride • Zatosetron; Atypical antipsychotics: Clozapine • Olanzapine • Quetiapine; Tetracyclic antidepressants: Amoxapine • Mianserin • Mirtazapine; Others: CSP-2503 • ICS-205,930 • MDL-72,222 • Memantine • Nitrous Oxide • Ricasetron • Sevoflurane • Tedatioxetine • Thujone • Vortioxetine • Xenon

5-HT₄	Agonists: Gastroprokinetic Agents: Cinitapride • Cisapride • Dazopride • Metoclopramide • Mosapride • Prucalopride • Renzapride • Tegaserod • Velusetrag • Zacopride; Others: 5-MT • BIMU8 • CJ-033,466 • PRX-03140 • RS-67333 • RS-67506 • SL65.0155 • Antagonists: GR-113,808 • GR-125,487 • L-Lysine • Piboserod • RS-39604 • RS-67532 • SB-203,186 • SB-204,070

5-HT_5A	Agonists: Lysergamides: Ergotamine • LSD; Tryptamines: 5-CT; Others: Valerenic Acid Antagonists: Asenapine • Latrepirdine • Metitepine/Methiothepin • Ritanserin • SB-699,551 * Note that the 5-HT_5B receptor is not functional in humans.

5-HT₆	Agonists: Lysergamides: Dihydroergotamine • Ergotamine • Lisuride • LSD • Mesulergine • Metergoline • Methysergide; Tryptamines: 2-Methyl-5-HT • 5-BT • 5-CT • 5-MT • Bufotenin • E-6801 • E-6837 • EMD-386,088 • EMDT • LY-586,713 • N-Methyl-5-HT • Tryptamine; Others: WAY-181,187 • WAY-208,466 Antagonists: Antidepressants: Amitriptyline • Amoxapine • Clomipramine • Doxepin • Mianserin • Nortriptyline; Atypical antipsychotics: Aripiprazole • Asenapine • Clorotepine • Clozapine • Fluperlapine • Iloperidone • Olanzapine • Tiospirone; Typical antipsychotics: Chlorpromazine • Loxapine; Others: BGC20-760 • BVT-5182 • BVT-74316 • Cerlapirdine • EGIS-12,233 • GW-742,457 • Ketanserin • Latrepirdine • Lu AE58054 • Metitepine/Methiothepin • MS-245 • PRX-07034 • Ritanserin • Ro04-6790 • Ro 63-0563 • SB-258,585 • SB-271,046 • SB-357,134 • SB-399,885 • SB-742,457

5-HT₇	Agonists: Lysergamides: LSD; Tryptamines: 5-CT • 5-MT • Bufotenin; Others: 8-OH-DPAT • AS-19 • Bifeprunox • E-55888 • LP-12 • LP-44 • RU-24,969 • Sarizotan Antagonists: Lysergamides: 2-Bromo-LSD • Bromocriptine • Dihydroergotamine • Ergotamine • Mesulergine • Metergoline • Methysergide; Antidepressants: Amitriptyline • Amoxapine • Clomipramine • Imipramine • Maprotiline • Mianserin; Atypical antipsychotics: Amisulpride • Aripiprazole • Clorotepine • Clozapine • Olanzapine • Risperidone • Sertindole • Tiospirone • Ziprasidone • Zotepine; Typical antipsychotics: Chlorpromazine • Loxapine; Others: Butaclamol • EGIS-12,233 • Ketanserin • LY-215,840 • Metitepine/Methiothepin • Pimozide • Ritanserin • SB-258,719 • SB-258,741 • SB-269,970 • SB-656,104 • SB-656,104-A • SB-691,673 • SLV-313 • SLV-314 • Spiperone • SSR-181,507 • Vortioxetine

Reuptake inhibitors

SERT	Selective serotonin reuptake inhibitors (SSRIs): Alaproclate • Citalopram • Dapoxetine • Desmethylcitalopram • Desmethylsertraline • Escitalopram • Femoxetine • Fluoxetine • Fluvoxamine • Indalpine • Ifoxetine • Litoxetine • Lubazodone • Panuramine • Paroxetine • Pirandamine • RTI-353 • Seproxetine • Sertraline • Tedatioxetine • Vilazodone • Vortioxetine • Zimelidine; Serotonin-norepinephrine reuptake inhibitors (SNRIs): Bicifadine • Desvenlafaxine • Duloxetine • Eclanamine • Levomilnacipran • Milnacipran • Sibutramine • Venlafaxine; Serotonin-norepinephrine-dopamine reuptake inhibitors (SNDRIs): Brasofensine • Diclofensine • DOV-102,677 • DOV-21,947 • DOV-216,303 • NS-2359 • SEP-225289 • SEP-227,162 • Tesofensine; Tricyclic antidepressants (TCAs): Amitriptyline • Butriptyline • Cianopramine • Clomipramine • Desipramine • Dosulepin • Doxepin • Imipramine • Lofepramine • Nortriptyline • Pipofezine • Protriptyline • Trimipramine; Tetracyclic antidepressants (TeCAs): Amoxapine; Piperazines: Nefazodone • Trazodone; Antihistamines: Brompheniramine • Chlorphenamine • Diphenhydramine • Mepyramine/Pyrilamine • Pheniramine • Tripelennamine; Opioids: Pethidine • Methadone • Propoxyphene; Others: Cocaine • CP-39,332 • Cyclobenzaprine • Dextromethorphan • Dextrorphan • EXP-561 • Fezolamine • Mesembrine • Nefopam • PIM-35 • Pridefine • Roxindole • SB-649,915 • Ziprasidone

VMAT	Ibogaine • Reserpine • Tetrabenazine

Releasing agents

Aminoindanes: 5-IAI • AMMI • ETAI • MDAI • MDMAI • MMAI • TAI; Aminotetralins: 6-CAT • 8-OH-DPAT • MDAT • MDMAT; Oxazolines: 4-Methylaminorex • Aminorex • Clominorex • Fluminorex; Phenethylamines (also Amphetamines, Cathinones, Phentermines, etc): 2-Methyl-MDA • 4-CAB • 4-FA • 4-FMA • 4-HA • 4-MTA • 5-APDB • 5-Methyl-MDA • 6-APDB • 6-Methyl-MDA • AEMMA • Amiflamine • BDB • BOH • Brephedrone • Butylone • Chlorphentermine • Cloforex • Amfepramone • Metamfepramone • DCA • DFMDA • DMA • DMMA • EBDB • EDMA • Ethylone • Etolorex • Fenfluramine (Dexfenfluramine) • Flephedrone • IAP • IMP • Lophophine • MBDB • MDA • MDEA • MDHMA • MDMA • MDMPEA • MDOH • MDPEA • Mephedrone • Methedrone • Methylone • MMA • MMDA • MMDMA • MMMA • NAP • Norfenfluramine • 4-TFMA • pBA • pCA • pIA • PMA • PMEA • PMMA • TAP; Piperazines: 2C-B-BZP • 2-BZP • 3-MeOPP • BZP • DCPP • MBZP • mCPP • MDBZP • MeOPP • Mepiprazole • pCPP • pFPP • pTFMPP • TFMPP; Tryptamines: 4-Methyl-αET • 4-Methyl-αMT • 5-CT • 5-MeO-αET • 5-MeO-αMT • 5-MT • αET • αMT • DMT • Tryptamine (itself); Others: Indeloxazine • Tramadol • Viqualine

Enzyme inhibitors

Anabolism

TPH	AGN-2979 • Fenclonine

AAAD	Benserazide • Carbidopa • Genistein • Methyldopa

Catabolism

MAO

Nonselective: Benmoxin • Caroxazone • Echinopsidine • Furazolidone • Hydralazine • Indantadol • Iproclozide • Iproniazid • Isocarboxazid • Isoniazid • Linezolid • Mebanazine • Metfendrazine • Nialamide • Octamoxin • Paraxazone • Phenelzine • Pheniprazine • Phenoxypropazine • Pivalylbenzhydrazine • Procarbazine • Safrazine • Tranylcypromine; MAO-A Selective: Amiflamine • Bazinaprine • Befloxatone • Befol • Brofaromine • Cimoxatone • Clorgiline • Esuprone • Harmala alkaloids (Harmine, Harmaline, Tetrahydroharmine, Harman, Norharman, etc) • Methylene Blue • Metralindole • Minaprine • Moclobemide • Pirlindole • Sercloremine • Tetrindole • Toloxatone • Tyrima

Others

Precursors	L-Tryptophan → 5-HTP

Cofactors	Ferrous iron (Fe²⁺) • Magnesium (Mg²⁺) • Tetrahydrobiopterin • Vitamin B₃ (Niacin, Nicotinamide → NADPH) • Vitamin B₆ (Pyridoxine, Pyridoxamine, Pyridoxal → Pyridoxal phosphate) • Vitamin B₉ (Folic Acid → Tetrahydrofolic acid) • Vitamin C (Ascorbic acid) • Zinc (Zn²⁺)

Others	Activity enhancers: BPAP • PPAP; Reuptake enhancers: Tianeptine

Tryptamines

2-Methyl-5-HT • 4-Acetoxy-DET • 4-Acetoxy-DiPT • 4-Acetoxy-DMT • 4-Acetoxy-MiPT • 4-AcO-MET • 4-HO-αMT • 4-HO-DiPT • 4-HO-MET • 4-MeO-DMT • 4-Methyl-αET • 4-Methyl-αMT • 4,5-DHP-DMT • 4,5-MDO-DMT • 4,5-MDO-DIPT • 5-Benzyloxytryptamine • 5-Bromo-DMT • 5-Carboxamidotryptamine • 5-Ethoxy-αMT • 5-Fluoro-αMT • 5-HO-αMT • 5-HTP • 5-Ethoxy-DMT • 5-Ethyl-DMT • 5-Fluoro-DMT • 5-Methyl-DMT • 5-Methoxytryptamine • 5-MeO-7,N,N-TMT • 5-Methyl-αET • 5-MeO-αET • 5-MeO-αMT • 5-MeO-DALT • 5-MeO-DET • 5-MeO-DiPT • 5-MeO-DMT • 5-MeO-DPT • 5-MeO-MALT • 5-MeO-MiPT • 5-MeO-NBpBrT • 5,7-Dihydroxytryptamine • 5-(Nonyloxy)tryptamine • 6-Fluoro-αMT • 7-Methyl-αET • 7-Methyl-DMT • αET • αMT • Aeruginascin • AL-37350A • BW-723C86 • Baeocystin • Bufotenidine • Bufotenin • DALT • Desformylflustrabromine • DET • DiPT • DMT • DPT • Ethocybin • EiPT • EMDT • EPT • Ethocin • FGIN-127 • FGIN-143 • Ibogaine • Indorenate • Iprocin • MET • MiPT • MPT • Miprocin • Melatonin • MS-245 • NAS • NMT • Norbaeocystin • Normelatonin • Oxypertine • PiPT • Psilocin • Psilocybin • Rizatriptan • Serotonin • Sumatriptan • Tryptamine • Tryptophan • Yohimbine • Yuremamine • Zolmitriptan

5-Hydroxytryptophan

Contents

Metabolism

Pharmacology

Dietary sources

Therapeutic use

Possible risks or side effects

See also

References

Further reading