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Wikipedia

5-Hydroxytryptophan

August 29, 2023

Not to be confused with 5-hydroxytryptamine.

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

5-Hydroxytryptophan
Names
IUPAC name
2-amino-3-(5-hydroxy-1H-indol-3-yl)propanoic acid
Identifiers
  • 4350-09-8 N
3D model (JSmol)
  • Interactive image
ChEBI
  • CHEBI:17780 Y
ChEMBL
  • ChEMBL350221 Y
ChemSpider
  • 388413 Y
ECHA InfoCard 100.022.193
  • 4671
KEGG
  • D07339 Y
MeSH 5-Hydroxytryptophan
  • 144
UNII
  • C1LJO185Q9 Y
  • DTXSID1025437
  • 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
  • O=C(O)[C@@H](N)Cc2c1cc(O)ccc1[nH]c2
Properties
C11H12N2O3
Molar mass 220.228 g·mol−1
Density 1.484 g/mL
Melting point 298 to 300 °C (568 to 572 °F; 571 to 573 K)
Boiling point 520.6 °C (969.1 °F; 793.8 K)
Pharmacology
N06AX01 (WHO)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N verify (what is YN ?)

Uses Edit

5-HTP is sold over the counter in the United States, France, Canada, Singapore, the Netherlands, and the United Kingdom as a dietary supplement for use as an antidepressant, appetite suppressant, and sleep aid. It is also marketed in many European countries for the indication of major depression under the trade names Cincofarm, Levothym, Levotonine, Oxyfan, Telesol, Tript-OH, and Triptum.[1]

A 2002 review concluded that although the data evaluated suggests that 5-HTP is more effective than placebo in the treatment of depression, the evidence was insufficient to be conclusive due to a lack of clinical data meeting the rigorous standards of the day.[2] More and larger studies using current methodologies are needed to determine if 5-HTP is truly effective in treating depression.[3][4] In small, controlled trials 5-HTP has also been reported to augment the antidepressant efficacy of the antidepressant clomipramine.[5][6][7] A 2020 meta-analysis found oral 5-HTP supplementation had a large effect size on depression symptom severity. However, the included studies were considered relatively weak and the methods and treatment duration varied between the seven studies examined.[8]

5-HTP use after MDMA

MDMA is an empathogenic-entactogenic and serotonergic psychotropic drug used primarily for recreational, though sometimes also therapeutic, purposes. Among users of MDMA, the serotonergic effects of the drug are often of particular interest and concern: After consuming MDMA, serotonin concentrations are greatly reduced in the brain. 5-HTP is necessary for serotonin production and its concentrations in the brain also decrease after taking MDMA. Additionally, tryptophan hydroxylase (a precursor to 5-HTP) concentrations are significantly reduced by MDMA use.[9] Tryptophan hydroxylase is a necessary precursor to 5-HTP.[10]

Other usage

At high doses, or in combination with carbidopa, 5-HTP has been used to treat obesity (by promoting weight loss).[11][12]

In clinical trials of various design, 5-HTP has also been reported to treat fibromyalgia,[13] myoclonus,[14] migraine,[15] and cerebellar ataxia.[16] However, these clinical findings, as for all therapeutic findings with 5-HTP, are preliminary and need confirmation in larger trials.

Drawbacks Edit

5-HTP's short half-life (<2h)[17] may inherently limit its therapeutic potential,[18] as systemic 5-HTP exposure levels will fluctuate substantially even with relatively frequent dosing. Such exposure fluctuations are usually associated with increased adverse event burdens resulting from Cmax (time to maximal systemic concentration) drug spikes, and decreased clinical efficacy resulting from sub-therapeutic exposure for large parts of the day, when taken as a single dose unit or at intervals significantly larger than Cmax. It has been proposed that 5-HTP dosage forms achieving prolonged delivery would be more effective,[18] as has been demonstrated many times with other pharmaceuticals with short durations of action.[19] For example, controlled release oxycodone (OxyContin) or morphine (MS-Contin) are intended to, via novel delivery mechanisms, permit pain relief for up to twelve hours with an active ingredient which only provides relief for 3–6 hours. However, the inherent variability amongst different people with respect to drug metabolism makes this task challenging.

Side effects Edit

Potential side effects of 5-HTP include heartburn, stomach pain, nausea, vomiting, diarrhea, drowsiness, sexual problems, vivid dreams or nightmares, and muscle problems.[20] Because 5-HTP has not been thoroughly studied in a clinical setting, possible side effects and interactions with other drugs are not well known. According to the US National Library of Medicine, 5-HTP has not been associated with serotonin syndrome or any serious adverse events in humans.[21] Across multiple studies, 5-HTP has also been reported to not cause any noticeable hematological or cardiovascular changes.[22] 5-HTP had also been associated with eosinophilia, but later studies have not found any causal connection.[23]

Interactions Edit

When combined with antidepressants of the MAOI or SSRI class, very high parenteral doses of 5-HTP can cause acute serotonin syndrome in rats.[24][25] It is unclear if such findings have clinical relevance, as most drugs will cause serious adverse events or death in rodents at very high doses. In humans 5-HTP has never been clinically associated with serotonin syndrome, although a case report suggests 5-HTP can precipitate mania when added to an MAOI.[26]

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.[27] As mentioned below under pharmacology, cases of scleroderma-like illness have been reported in patients using carbidopa and 5-HTP.[28]

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 false positive results in tests looking for carcinoid syndrome.[29][30] Due to the conversion of 5-HTP into serotonin by the liver, there could be a risk of heart valve disease from serotonin's effect on the heart, as based on preclinical findings.[31][32] However, 5-HTP has not been associated with cardiac toxicity in humans.[23][22][21][33]

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.[34]

Production Edit

5-HTP is produced from the amino acid tryptophan through the action of the enzyme tryptophan hydroxylase. Tryptophan hydroxylase is one of the biopterin-dependent aromatic amino acid hydroxylases. Production of 5-HTP is the rate-limiting step in 5-HT (serotonin) synthesis. 5-HTP is normally rapidly converted to 5-HT by amino acid decarboxylase.[35]

Absorption Edit

After oral administration, 5-HTP is absorbed by the upper intestine.[17] The mode of absorption is not known, but presumably involves active transport via amino acid transporters. 5-HTP is adequately absorbed via oral cavity.[36] With a decarboxylase inhibitor, the bioavailability of 5-HTP can be higher than 50%.[37]

Pharmacokinetics Edit

5-HTP is rapidly absorbed with a tmax of ≈1.5 h, and rapidly eliminated with a half-life of ≈1.5 – 2 h. Co-administration of a decarboxylase inhibitor (e.g. carbidopa, benserazide) doubles the half-life of 5-HTP to ≈ 3 – 4 h,[38][17] and enhances exposure several-fold, depending on the dosing regimen.[17][39]

Metabolism Edit

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.[40] This reaction occurs both in nervous tissue and in the liver.[41] 5-HTP crosses the blood–brain barrier,[42] while 5-HT does not. Excess 5-HTP, especially when administered with vitamin B6, is thought to be metabolized and excreted.[43][44]

5-HTP AAAD Serotonin
     
PLP
 
 
 


Pharmacology Edit

The psychoactive action of 5-HTP is derived from its increase in production of serotonin in central nervous system tissue.[45]

 
Metabolic pathway from tryptophan to serotonin.

Research shows that co-administration with carbidopa greatly increases plasma 5-HTP levels.[46] Other studies have indicated the risk of a scleroderma-like condition resulting from the combination of 5-HTP and carbidopa.[47]

Regulatory status Edit

There are currently no approved drug products containing 5-HTP approved by the FDA.[48] All available 5-HTP products are nutraceuticals and are as such not regulated or verified for purity, integrity, or clinical efficacy or safety, mandating caution regarding human consumption.[49]

As of 25 August 2020, Hungary added 5-HTP to the controlled psychoactive substances list, prohibiting production, sale, import, storage and use, becoming the first country to do so.[50]

5-HTP slow-release Edit

5-HTP's short half-life is impractical for chronic drug therapy. Research conducted at Duke University in mice have demonstrated that 5-HTP when administered as slow-release appears to gain drug properties.[51] Slow-release delivery attenuates or abolishes the peaks and valleys in 5-HTP exposure during treatment.[52] Slow-release delivery of 5-HTP markedly improved the safety profile of 5-HTP and conferred stable plasma exposure of 5-HTP and strong and sustained enhancement of brain serotonin function.[51] This discovery indicates that 5-HTP slow-release medications represent a new avenue for treatment of brain disorders responsive to serotonergic enhancement.

Dietary sources Edit

See also: Tryptophan § 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 all unfractionated foods, with lower total amino acid content correlating with increased tryptophan absorption.[53]

The seeds of the Griffonia simplicifolia, a climbing shrub native to West Africa and Central Africa, are used as an herbal supplement for their 5-HTP content.[54][55][56] In one 2010 trial, Griffonia simplicifolia extract appeared to increase satiety in overweight women.[57]

See also Edit

References Edit

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August 29, 2023
hydroxytryptophan, confused, with, hydroxytryptamine, also, known, oxitriptan, naturally, occurring, amino, acid, chemical, precursor, well, metabolic, intermediate, biosynthesis, neurotransmitter, serotonin, namesiupac, name, amino, hydroxy, indol, propanoic,. Not to be confused with 5 hydroxytryptamine 5 Hydroxytryptophan 5 HTP also known as oxitriptan is a naturally occurring amino acid and chemical precursor as well as a metabolic intermediate in the biosynthesis of the neurotransmitter serotonin 5 Hydroxytryptophan NamesIUPAC name 2 amino 3 5 hydroxy 1H indol 3 yl propanoic acidIdentifiersCAS Number 4350 09 8 N3D model JSmol Interactive imageChEBI CHEBI 17780 YChEMBL ChEMBL350221 YChemSpider 388413 YECHA InfoCard 100 022 193IUPHAR BPS 4671KEGG D07339 YMeSH 5 HydroxytryptophanPubChem CID 144UNII C1LJO185Q9 YCompTox Dashboard EPA DTXSID1025437InChI 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 YKey LDCYZAJDBXYCGN VIFPVBQESA N YInChI 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 s1Key LDCYZAJDBXYCGN VIFPVBQEBZSMILES O C O C H N Cc2c1cc O ccc1 nH c2PropertiesChemical formula C 11H 12N 2O 3Molar mass 220 228 g mol 1Density 1 484 g mLMelting point 298 to 300 C 568 to 572 F 571 to 573 K Boiling point 520 6 C 969 1 F 793 8 K PharmacologyATC code N06AX01 WHO Except where otherwise noted data are given for materials in their standard state at 25 C 77 F 100 kPa N verify what is Y N Infobox references Contents 1 Uses 2 Drawbacks 3 Side effects 4 Interactions 5 Production 6 Absorption 7 Pharmacokinetics 8 Metabolism 9 Pharmacology 10 Regulatory status 11 5 HTP slow release 12 Dietary sources 13 See also 14 ReferencesUses Edit5 HTP is sold over the counter in the United States France Canada Singapore the Netherlands and the United Kingdom as a dietary supplement for use as an antidepressant appetite suppressant and sleep aid It is also marketed in many European countries for the indication of major depression under the trade names Cincofarm Levothym Levotonine Oxyfan Telesol Tript OH and Triptum 1 A 2002 review concluded that although the data evaluated suggests that 5 HTP is more effective than placebo in the treatment of depression the evidence was insufficient to be conclusive due to a lack of clinical data meeting the rigorous standards of the day 2 More and larger studies using current methodologies are needed to determine if 5 HTP is truly effective in treating depression 3 4 In small controlled trials 5 HTP has also been reported to augment the antidepressant efficacy of the antidepressant clomipramine 5 6 7 A 2020 meta analysis found oral 5 HTP supplementation had a large effect size on depression symptom severity However the included studies were considered relatively weak and the methods and treatment duration varied between the seven studies examined 8 5 HTP use after MDMAMDMA is an empathogenic entactogenic and serotonergic psychotropic drug used primarily for recreational though sometimes also therapeutic purposes Among users of MDMA the serotonergic effects of the drug are often of particular interest and concern After consuming MDMA serotonin concentrations are greatly reduced in the brain 5 HTP is necessary for serotonin production and its concentrations in the brain also decrease after taking MDMA Additionally tryptophan hydroxylase a precursor to 5 HTP concentrations are significantly reduced by MDMA use 9 Tryptophan hydroxylase is a necessary precursor to 5 HTP 10 Other usageAt high doses or in combination with carbidopa 5 HTP has been used to treat obesity by promoting weight loss 11 12 In clinical trials of various design 5 HTP has also been reported to treat fibromyalgia 13 myoclonus 14 migraine 15 and cerebellar ataxia 16 However these clinical findings as for all therapeutic findings with 5 HTP are preliminary and need confirmation in larger trials Drawbacks Edit5 HTP s short half life lt 2h 17 may inherently limit its therapeutic potential 18 as systemic 5 HTP exposure levels will fluctuate substantially even with relatively frequent dosing Such exposure fluctuations are usually associated with increased adverse event burdens resulting from Cmax time to maximal systemic concentration drug spikes and decreased clinical efficacy resulting from sub therapeutic exposure for large parts of the day when taken as a single dose unit or at intervals significantly larger than Cmax It has been proposed that 5 HTP dosage forms achieving prolonged delivery would be more effective 18 as has been demonstrated many times with other pharmaceuticals with short durations of action 19 For example controlled release oxycodone OxyContin or morphine MS Contin are intended to via novel delivery mechanisms permit pain relief for up to twelve hours with an active ingredient which only provides relief for 3 6 hours However the inherent variability amongst different people with respect to drug metabolism makes this task challenging Side effects EditPotential side effects of 5 HTP include heartburn stomach pain nausea vomiting diarrhea drowsiness sexual problems vivid dreams or nightmares and muscle problems 20 Because 5 HTP has not been thoroughly studied in a clinical setting possible side effects and interactions with other drugs are not well known According to the US National Library of Medicine 5 HTP has not been associated with serotonin syndrome or any serious adverse events in humans 21 Across multiple studies 5 HTP has also been reported to not cause any noticeable hematological or cardiovascular changes 22 5 HTP had also been associated with eosinophilia but later studies have not found any causal connection 23 Interactions EditWhen combined with antidepressants of the MAOI or SSRI class very high parenteral doses of 5 HTP can cause acute serotonin syndrome in rats 24 25 It is unclear if such findings have clinical relevance as most drugs will cause serious adverse events or death in rodents at very high doses In humans 5 HTP has never been clinically associated with serotonin syndrome although a case report suggests 5 HTP can precipitate mania when added to an MAOI 26 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 27 As mentioned below under pharmacology cases of scleroderma like illness have been reported in patients using carbidopa and 5 HTP 28 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 false positive results in tests looking for carcinoid syndrome 29 30 Due to the conversion of 5 HTP into serotonin by the liver there could be a risk of heart valve disease from serotonin s effect on the heart as based on preclinical findings 31 32 However 5 HTP has not been associated with cardiac toxicity in humans 23 22 21 33 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 34 Production Edit5 HTP is produced from the amino acid tryptophan through the action of the enzyme tryptophan hydroxylase Tryptophan hydroxylase is one of the biopterin dependent aromatic amino acid hydroxylases Production of 5 HTP is the rate limiting step in 5 HT serotonin synthesis 5 HTP is normally rapidly converted to 5 HT by amino acid decarboxylase 35 Absorption EditAfter oral administration 5 HTP is absorbed by the upper intestine 17 The mode of absorption is not known but presumably involves active transport via amino acid transporters 5 HTP is adequately absorbed via oral cavity 36 With a decarboxylase inhibitor the bioavailability of 5 HTP can be higher than 50 37 Pharmacokinetics Edit5 HTP is rapidly absorbed with a tmax of 1 5 h and rapidly eliminated with a half life of 1 5 2 h Co administration of a decarboxylase inhibitor e g carbidopa benserazide doubles the half life of 5 HTP to 3 4 h 38 17 and enhances exposure several fold depending on the dosing regimen 17 39 Metabolism Edit5 HTP is decarboxylated to serotonin 5 hydroxytryptamine or 5 HT by the enzyme aromatic L amino acid decarboxylase with the help of vitamin B6 40 This reaction occurs both in nervous tissue and in the liver 41 5 HTP crosses the blood brain barrier 42 while 5 HT does not Excess 5 HTP especially when administered with vitamin B6 is thought to be metabolized and excreted 43 44 5 HTP AAAD Serotonin PLP Pharmacology EditThe psychoactive action of 5 HTP is derived from its increase in production of serotonin in central nervous system tissue 45 Metabolic pathway from tryptophan to serotonin Research shows that co administration with carbidopa greatly increases plasma 5 HTP levels 46 Other studies have indicated the risk of a scleroderma like condition resulting from the combination of 5 HTP and carbidopa 47 Regulatory status EditThere are currently no approved drug products containing 5 HTP approved by the FDA 48 All available 5 HTP products are nutraceuticals and are as such not regulated or verified for purity integrity or clinical efficacy or safety mandating caution regarding human consumption 49 As of 25 August 2020 Hungary added 5 HTP to the controlled psychoactive substances list prohibiting production sale import storage and use becoming the first country to do so 50 5 HTP slow release Edit5 HTP s short half life is impractical for chronic drug therapy Research conducted at Duke University in mice have demonstrated that 5 HTP when administered as slow release appears to gain drug properties 51 Slow release delivery attenuates or abolishes the peaks and valleys in 5 HTP exposure during treatment 52 Slow release delivery of 5 HTP markedly improved the safety profile of 5 HTP and conferred stable plasma exposure of 5 HTP and strong and sustained enhancement of brain serotonin function 51 This discovery indicates that 5 HTP slow release medications represent a new avenue for treatment of brain disorders responsive to serotonergic enhancement Dietary sources EditSee also Tryptophan 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 all unfractionated foods with lower total amino acid content correlating with increased tryptophan absorption 53 The seeds of the Griffonia simplicifolia a climbing shrub native to West Africa and Central Africa are used as an herbal supplement for their 5 HTP content 54 55 56 In one 2010 trial Griffonia simplicifolia extract appeared to increase satiety in overweight women 57 See also EditCardiac fibrosis Melatonin N Acetylserotonin Selective serotonin reuptake inhibitor Serotonin TryptophanReferences Edit Swiss Pharmaceutical Society 2000 Index Nominum 2000 International Drug Directory Book with CD ROM Boca Raton Medpharm Scientific Publishers ISBN 978 3 88763 075 1 Shaw K Turner J Del Mar C 2002 Shaw KA ed Tryptophan and 5 hydroxytryptophan for depression PDF The Cochrane Database of Systematic Reviews 2010 1 CD003198 doi 10 1002 14651858 CD003198 PMID 11869656 5 Hydroxytryptophan 5 HTP University of Maryland Medical Center Archived from the original on 25 June 2017 Retrieved 9 January 2012 Iovieno N Dalton ED Fava M Mischoulon D May 2011 Second tier natural antidepressants review and critique Journal of Affective Disorders 130 3 343 357 doi 10 1016 j jad 2010 06 010 PMID 20579741 van Praag HM 1982 Serotonin precursors in the treatment of depression Advances in Biochemical Psychopharmacology 34 259 286 PMID 6753514 van Praag HM van den Burg W Bos ER Dols LC 1974 5 hydroxytryptophan in combination with clomipramine in therapy resistant depressions Psychopharmacologia 38 3 267 269 doi 10 1007 BF00421379 PMID 4547418 S2CID 11048888 Nardini M De Stefano R Iannuccelli M Borghesi R Battistini N 1983 Treatment of depression with L 5 hydroxytryptophan combined with chlorimipramine a double blind study International Journal of Clinical Pharmacology Research 3 4 239 250 PMID 6381336 Javelle Florian Lampit Amit Bloch Wilhelm Haussermann Peter Johnson Sheri Zimmer Philipp 2020 Effects of 5 hydroxytryptophan on distinct types of depression a systematic review and meta analysis Nutrition Reviews 78 1 77 88 doi 10 1093 nutrit nuz039 PMID 31504850 Xie Tao Tong Liqiong McLane Michael W Hatzidimitriou George Yuan Jie McCann Una Ricaurte George December 2006 Loss of Serotonin Transporter Protein after MDMA and Other Ring Substituted Amphetamines Neuropsychopharmacology 31 12 2639 2651 doi 10 1038 sj npp 1301031 ISSN 1740 634X PMID 16452989 S2CID 13070928 Massimo Maffei 26 December 2020 5 Hydroxytryptophan 5 HTP Natural Occurrence Analysis Biosynthesis Biotechnology Physiology and Toxicology International Journal of Molecular Sciences 22 1 181 doi 10 3390 ijms22010181 PMC 7796270 PMID 33375373 Halpern B Oliveira ES Faria AM Halpern A Melo ME Cercato C Mancini MC July 2010 Combinations of drugs in the Treatment of Obesity Pharmaceuticals 3 8 2398 2415 doi 10 3390 ph3082398 PMC 4033931 PMID 27713360 Hendricks EJ 2017 Off label drugs for weight management Diabetes Metabolic Syndrome and Obesity Targets and Therapy 10 223 234 doi 10 2147 DMSO S95299 PMC 5473499 PMID 28652791 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 J Int Med Res 18 3 201 209 doi 10 1177 030006059001800304 PMID 2193835 S2CID 27586915 Thal LJ Sharpless NS Wolfson L Katzman R 1980 Treatment of myoclonus with L 5 hydroxytryptophan and carbidopa clinical electrophysiological and biochemical observations Ann Neurol 7 6 570 576 doi 10 1002 ana 410070611 PMID 6969054 S2CID 11647568 Boiardi A Crenna P Merati B Negri S Tansini E Bussone G 1981 5 OH Tryptophane in migraine clinical and neurophysiological considerations J Neurol 225 1 41 46 doi 10 1007 bf00313460 PMID 6164755 S2CID 2424064 Trouillas P Brudon F Adeleine P November 1988 Improvement of cerebellar ataxia with levorotatory form of 5 hydroxytryptophan A double blind study with quantified data processing Arch Neurol 45 11 1217 1222 doi 10 1001 archneur 1988 00520350055016 PMID 3190503 a b c d Gijsman HJ van Gerven JM de Kam ML Schoemaker RC Pieters MS Weemaes M de Rijk R van der Post J Cohen AF April 2002 Placebo controlled comparison of three dose regimens of 5 hydroxytryptophan challenge test in healthy volunteers Journal of Clinical Psychopharmacology 22 2 183 189 doi 10 1097 00004714 200204000 00012 PMID 11910264 S2CID 37414452 a b Jacobsen JP Krystal AD Krishnan KR Caron MG November 2016 Adjunctive 5 Hydroxytryptophan Slow Release for Treatment Resistant Depression Clinical and Preclinical Rationale Trends in Pharmacological Sciences 37 11 933 944 doi 10 1016 j tips 2016 09 001 PMC 5728156 PMID 27692695 Thombre AG September 2005 Assessment of the feasibility of oral controlled release in an exploratory development setting Drug Discovery Today 10 17 1159 1166 doi 10 1016 S1359 6446 05 03551 8 PMID 16182208 5 HTP U S National Library of Medicine Retrieved 7 June 2015 a b 5 Hydroxytryptophan C11H12N2O3 CID 144 PubChem a b Byerley WF Judd LL Reimherr FW Grosser BI June 1987 5 Hydroxytryptophan a review of its antidepressant efficacy and adverse effects J Clin Psychopharmacol 7 3 127 37 doi 10 1097 00004714 198706000 00002 PMID 3298325 a b Das YT Bagchi M Bagchi D Preuss HG 2004 Safety of 5 hydroxy L tryptophan Toxicol Lett 150 1 111 22 doi 10 1016 j toxlet 2003 12 070 PMID 15068828 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 European Journal of Pharmacology 588 2 3 198 206 doi 10 1016 j ejphar 2008 04 004 PMC 4242171 PMID 18499101 Izumi T Iwamoto N Kitaichi Y Kato A Inoue T Koyama T February 2006 Effects of co administration of a selective serotonin reuptake inhibitor and monoamine oxidase inhibitors on 5 HT related behavior in rats European Journal of Pharmacology 532 3 258 64 doi 10 1016 j ejphar 2005 12 075 PMID 16488409 Pardo JV 2012 Mania following addition of hydroxytryptophan to monoamine oxidase inhibitor General Hospital Psychiatry 34 1 102 e13 4 doi 10 1016 j genhosppsych 2011 08 014 PMC 3253963 PMID 21963353 Jacobs GE Kamerling IM de Kam ML Derijk RH van Pelt J Zitman FG van Gerven JM January 2010 Enhanced tolerability of the 5 hydroxytryptophane challenge test combined with granisetron Journal of Psychopharmacology 24 1 65 72 doi 10 1177 0269881108094299 PMID 18719048 S2CID 23562225 Carbidopa Levodopa Truestarhealth com Archived from the original on 8 January 2014 Retrieved 2014 01 09 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 Canadian Journal of Gastroenterology 22 1 49 53 doi 10 1155 2008 472159 PMC 2659120 PMID 18209781 Hallin ML Mahmoud K Viswanath A Gama R January 2013 Sweet Dreams Happy Days and elevated 24 h urine 5 hydroxyindoleacetic acid excretion Annals of Clinical Biochemistry 50 Pt 1 80 2 doi 10 1258 acb 2012 012041 PMID 23086978 S2CID 207193834 Gustafsson BI Tommeras K Nordrum I Loennechen JP Brunsvik A Solligard 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 S2CID 3035838 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 The American Journal of Pathology 161 6 2209 18 doi 10 1016 S0002 9440 10 64497 5 PMC 1850896 PMID 12466135 Turner EH Loftis JM Blackwell AD March 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 S2CID 2563606 Michelson D Page SW Casey R Trucksess MW Love LA Milstien S Wilson C Massaquoi SG Crofford LJ Hallett M December 1994 An eosinophilia myalgia syndrome related disorder associated with exposure to L 5 hydroxytryptophan The Journal of Rheumatology 21 12 2261 5 PMID 7699627 Turner EH Loftis JM Blackwell AD March 2006 Serotonin a la carte supplementation with the serotonin precursor 5 hydroxytryptophan Pharmacology amp Therapeutics 109 3 325 38 doi 10 1016 j pharmthera 2005 06 004 PMID 16023217 S2CID 2563606 Rondanelli M Opizzi A Faliva M Bucci M Perna S March 2012 Relationship between the absorption of 5 hydroxytryptophan from an integrated diet by means of Griffonia simplicifolia extract and the effect on satiety in overweight females after oral spray administration Eat Weight Disord 17 1 e22 8 doi 10 3275 8165 PMID 22142813 S2CID 10651414 Magnussen I Nielsen Kudsk F April 1980 Bioavailability and related pharmacokinetics in man of orally administered L 5 hydroxytryptophan in steady state Acta Pharmacologica et Toxicologica 46 4 257 62 doi 10 1111 j 1600 0773 1980 tb02451 x PMID 6966118 Magnussen I Engbaek F July 1978 The effects of aromatic amino acid decarboxylase inhibitors on plasma concentrations of 5 hydroxytryptophan in man Acta Pharmacologica et Toxicologica 43 1 36 42 doi 10 1111 j 1600 0773 1978 tb02229 x PMID 309271 Westenberg HG Gerritsen TW Meijer BA van Praag HM December 1982 Kinetics of l 5 hydroxytryptophan in healthy subjects Psychiatry Research 7 3 373 85 doi 10 1016 0165 1781 82 90074 9 PMID 6187038 S2CID 45003287 Rahman MK Nagatsu T Sakurai T Hori S Abe M Matsuda M October 1982 Effect of pyridoxal phosphate deficiency on aromatic L amino acid decarboxylase activity with L DOPA and L 5 hydroxytryptophan as substrates in rats Japanese Journal of Pharmacology 32 5 803 11 doi 10 1254 jjp 32 803 PMID 6983619 Bouchard S Bousquet C Roberge AG September 1981 Characteristics of dihydroxyphenylalanine 5 hydroxytryptophan decarboxylase activity in brain and liver of cat Journal of Neurochemistry 37 3 781 7 doi 10 1111 j 1471 4159 1982 tb12555 x PMID 6974228 S2CID 43853143 Nakatani Y Sato Suzuki I Tsujino N Nakasato A Seki Y Fumoto M Arita H May 2008 Augmented brain 5 HT crosses the blood brain barrier through the 5 HT transporter in rat The European Journal of Neuroscience 27 9 2466 72 doi 10 1111 j 1460 9568 2008 06201 x PMID 18445233 S2CID 18940166 Bouchard S Roberge AG July 1979 Biochemical properties and kinetic parameters of dihydroxyphenylalanine 5 hydroxytryptophan decarboxylase in brain liver and adrenals of cat Canadian Journal of Biochemistry 57 7 1014 8 doi 10 1139 o79 126 PMID 39668 Amamoto T Sarai K September 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 Journal of Medical Sciences 25 2 3 135 40 PMID 1088369 5 HTP Uses Side Effects Interactions and Warnings WebMD Archived from the original on 16 November 2009 Retrieved 5 October 2009 Magnussen I Jensen TS Rand JH Van Woert MH September 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 Sternberg EM Van Woert MH Young SN Magnussen I Baker H Gauthier S Osterland CK October 1980 Development of a scleroderma like illness during therapy with L 5 hydroxytryptophan and carbidopa The New England Journal of Medicine 303 14 782 7 doi 10 1056 NEJM198010023031403 PMID 6997735 Orange Book Approved Drug Products with Therapeutic Equivalence Evaluations 5 HTP MedlinePlus Supplements MAGYARORSZAG HIVATALOS LAPJA Retrieved 2021 04 28 a b Jacobsen JP Rudder ML Roberts W Royer EL Robinson TJ Oh A Spasojevic I Sachs BD Caron MG August 2016 SSRI Augmentation by 5 Hydroxytryptophan Slow Release Mouse Pharmacodynamic Proof of Concept Neuropsychopharmacology 41 9 2324 34 doi 10 1038 npp 2016 35 PMC 4946063 PMID 26932820 Thombre AG 2005 Assessment of the feasibility of oral controlled release in an exploratory development setting Drug Discov Today 10 17 1159 66 doi 10 1016 S1359 6446 05 03551 8 PMID 16182208 5 Hydroxytryptophan University of Maryland Medical Center Archived from the original on 6 January 2010 Retrieved 21 January 2010 5 Hydroxytryptophan 5 HTP A D A M Inc University of Maryland Medical Center Animated Dissection of Anatomy for Medicine Inc A D A M Inc provided health and benefits information and technology to healthcare organizations employers consumers and educational institutions Emanuele E Bertona M Minoretti P Geroldi D 2010 An open label trial of L 5 hydroxytryptophan in subjects with romantic stress Neuro Endocrinology Letters 31 5 663 6 PMID 21178946 5 hydroxy L tryptophan National Center for Biotechnology Information PubChem Compound Database September 2004 CID 439280 Rondanelli M Opizzi A Faliva M Bucci M Perna S March 2012 Relationship between the absorption of 5 hydroxytryptophan from an integrated diet by means of Griffonia simplicifolia extract and the effect on satiety in overweight females after oral spray administration Eating and Weight Disorders 17 1 e22 8 doi 10 3275 8165 PMID 22142813 S2CID 10651414 Retrieved from https en wikipedia org w index php title 5 Hydroxytryptophan amp oldid 1170953817, wikipedia, wiki, book, books, library,

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