Do I need a prescription for Tryptophan 50mg capsules?

Tryptophan 50mg capsules is classified as a Valid as a prescribable product in the UK. However, always consult a pharmacist or doctor before use. (Source: NHS dm+d)

What are the brand names for Tryptophan 50mg capsules?

Tryptophan 50mg capsules is the generic name. It is available under brand names including: Tryptophan 50mg capsules. (Source: NHS dm+d — Actual Medicinal Products)

Tryptophan 50mg capsules

Prescription only

Requires a prescription from a doctor or prescriber

Capsule

50mg

Oral

An essential amino acid that is necessary for normal growth in infants and for nitrogen balance in adults.

Active ingredients:

Tryptophan

BNF classificationBrowse formulary

Where this medicine sits in the British National Formulary — the UK's standard prescribing reference

BNF 04.03.04

ATC classificationBrowse ATC index

International classification by the WHO, grouping medicines by the organ system they act on

ATC N06AX02

Chemical classBrowse classes

Classification based on the molecule's chemical structure and properties

Check interactions for Tryptophan

No active safety alerts

Official documents, adverse reaction reporting, and safety monitoring

Report a side effect

Submit a Yellow Card report to the MHRA

Official medicine documents

Yellow Card

Report side effects (MHRA)

Drug safety updates

MHRA alerts for Tryptophan

Source: MHRA Products DatabaseOGL 3.0

Updated 3 months ago(16 Jan 2026)

Safety monitoring data

Yellow Card reports

MHRA

The MHRA Yellow Card scheme collects reports of suspected side effects from healthcare professionals and patients. View the Drug Analysis Profile (iDAP) for real-world adverse reaction data.

View Drug Analysis Profile

Suspected adverse reactions reported for Tryptophan

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Report a side effect

Submit a Yellow Card report to the MHRA

Data from the MHRA Yellow Card scheme. A reported reaction does not necessarily mean the medicine caused it. Contains public sector information licensed under the Open Government Licence v3.0.

EudraVigilance

EMA

The European Medicines Agency (EMA) collects suspected adverse reaction reports from across the EU/EEA through the EudraVigilance system. Search for safety data on this medicine.

View EudraVigilance report

Suspected adverse reactions reported for Tryptophan

About EudraVigilance

Learn about EU pharmacovigilance and safety monitoring

EudraVigilance data is published by the European Medicines Agency (EMA). A suspected adverse reaction is not necessarily caused by the medicine.

1 branded products available

1 productsShow details

1 products

Possibly available on the UK marketRestricted supplyDiscontinuedAvailability per NHS dm+d

MHRA licensed products

View all licensed products for Tryptophan on the MHRA register

Tryptophan 50mg capsules

Special Order

None

Special

Source: NHS dm+dOGL 3.0

Updated about 1 month ago(1 Mar 2026)

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Same therapeutic group

Similarity based on WHO Anatomical Therapeutic Chemical (ATC) classification and NHS BNF section grouping. Source data: NHS dm+d via TRUD (OGL v3.0), WHO ATC/DDD Index.

NHS prescribing volume and spending trends

Show details

Loading prescribing data...

Clinical guidelines and formulary information

British National Formulary

Tryptophan

BNF

Drug monograph — bnf.nice.org.uk

Source: British National Formulary, NICE. Joint Formulary Committee. Contains public sector information licensed under the Open Government Licence v3.0.

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Search for this medicine at major UK pharmacy chains. These links open the retailer's own website — results depend on their current online catalogue.

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Official product databases and supply status monitoring

Shortages info

NHS Specialist Pharmacy Service (SPS)

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Discontinuations & alternatives for Tryptophan

Pharmacy links redirect to the retailer's own search and do not represent real-time stock levels. emc (electronic medicines compendium) is operated by Datapharm Ltd. Shortage information sourced from NHS Specialist Pharmacy Service (SPS), sps.nhs.uk.

Codes for healthcare professionals and prescribing systems

Show details

These codes are used by healthcare IT systems and prescribers to identify this medicine.

NHS UK identifiers

SNOMED CT

13573711000001106

dm+d ID

13573711000001106

VTM (Virtual Therapeutic Moiety)

777880003

VMP (Virtual Medicinal Product)

13573711000001106

BNF code

04030400

International identifiers

ATC code — Anatomical Therapeutic Chemical (WHO)

N06AX02

Browse tools

dm+d Browser

NHSBSA medicines dictionary lookup

SNOMED CT and dm+d codes from NHS TRUD (Technology Reference data Update Distribution), licensed under the Open Government Licence v3.0. BNF codes from NHS Business Services Authority (NHSBSA). ATC codes from the WHO Collaborating Centre for Drug Statistics Methodology (whocc.no).

Active and completed clinical studies from ClinicalTrials.gov

Show details

Searching UK clinical trials...

Source: ClinicalTrials.gov, a database of the U.S. National Library of Medicine (NLM), National Institutes of Health (NIH). Data accessed via ClinicalTrials.gov API v2. Trial information is provided for research purposes and does not constitute medical advice.

Pharmacology and chemical data from DrugBank

go.drugbank.com

Key facts

Drug status

Approved

Major interactions

65 found

Half-life

Not available

Mechanism

A number of important side reactions occur during the catabolism of tryptophan on the pathway to acetoacetate.

Food interactions

None known

Human targets

3 targets

Data: DrugBank · CC BY-NC 4.0

Pharmacokinetics at a glance

Metabolism

Hepatic.

Pharmacokinetic data: DrugBank · CC BY-NC 4.0

Status:

Approved

Investigational

Nutraceutical

Withdrawn

Small molecule

About this compound

An essential amino acid that is necessary for normal growth in infants and for nitrogen balance in adults. It is a precursor of indole alkaloids in plants. It is a precursor of serotonin (hence its use as an antidepressant and sleep aid). It can be a precursor to niacin, albeit inefficiently, in mammals.

Properties:

solid

Avg. mass: 204.23 Da

DrugBank indication

Tryptophan may be useful in increasing serotonin production, promoting healthy sleep, managing depression by enhancing mental and emotional well-being, managing pain tolerance, and managing weight.

Also known as(91)

(2S)-2-amino-3-(1H-indol-3-yl)propanoic acid

(S)-alpha-Amino-beta-(3-indolyl)-propionic acid

(S)-Tryptophan

(S)-α-amino-1H-indole-3-propanoic acid

L-(-)-Tryptophan

L-(−)-tryptophan

L-Tryptophan

L-β-3-indolylalanine

Dosage forms(52)

Solution (Parenteral)

Tablet (Oral)

Solution (Intravenous) — 10.50 g/1000ml

Injection (Intravenous) — 0.5 g/l

Injection (Intravenous) — 0.25 g/1000ml

Solution, concentrate (Intravenous)

Injection (Intravenous) — 0.52 g/l

Liquid (Intravenous)

Molecular properties(19)

Drug interactions(703)

Known interactions with other medications. Always consult a healthcare professional.

Buprenorphine

Moderate

DB00921

Tryptophan may increase the central nervous system depressant (CNS depressant) activities of Buprenorphine.

Check this interaction

Doxylamine

Moderate

DB00366

Doxylamine may increase the central nervous system depressant (CNS depressant) activities of Tryptophan.

Check this interaction

Dronabinol

Moderate

DB00470

Dronabinol may increase the central nervous system depressant (CNS depressant) activities of Tryptophan.

Check this interaction

Droperidol

Moderate

DB00450

Droperidol may increase the central nervous system depressant (CNS depressant) activities of Tryptophan.

Check this interaction

Hydrocodone

Moderate

DB00956

Tryptophan may increase the central nervous system depressant (CNS depressant) activities of Hydrocodone.

Check this interaction

Hydroxyzine

Moderate

DB00557

Hydroxyzine may increase the central nervous system depressant (CNS depressant) activities of Tryptophan.

Check this interaction

Methotrimeprazine

Moderate

DB01403

Tryptophan may increase the central nervous system depressant (CNS depressant) activities of Methotrimeprazine.

Check this interaction

Metyrosine

Moderate

DB00765

Tryptophan may increase the sedative activities of Metyrosine.

Check this interaction

Minocycline

Moderate

DB01017

Minocycline may increase the central nervous system depressant (CNS depressant) activities of Tryptophan.

Check this interaction

Nabilone

Moderate

DB00486

Nabilone may increase the central nervous system depressant (CNS depressant) activities of Tryptophan.

Check this interaction

Orphenadrine

Moderate

DB01173

Tryptophan may increase the central nervous system depressant (CNS depressant) activities of Orphenadrine.

Check this interaction

Paraldehyde

Moderate

DB09117

Tryptophan may increase the central nervous system depressant (CNS depressant) activities of Paraldehyde.

Check this interaction

Perampanel

Moderate

DB08883

Perampanel may increase the central nervous system depressant (CNS depressant) activities of Tryptophan.

Check this interaction

Pramipexole

Moderate

DB00413

Tryptophan may increase the sedative activities of Pramipexole.

Check this interaction

Ropinirole

Moderate

DB00268

Tryptophan may increase the sedative activities of Ropinirole.

Check this interaction

Rotigotine

Moderate

DB05271

Tryptophan may increase the sedative activities of Rotigotine.

Check this interaction

Rufinamide

Unknown severity

DB06201

The risk or severity of adverse effects can be increased when Rufinamide is combined with Tryptophan.

Check this interaction

Sodium oxybate

Moderate

DB09072

Tryptophan may increase the central nervous system depressant (CNS depressant) activities of Sodium oxybate.

Check this interaction

Suvorexant

Moderate

DB09034

Tryptophan may increase the central nervous system depressant (CNS depressant) activities of Suvorexant.

Check this interaction

Tapentadol

Moderate

DB06204

Tapentadol may increase the central nervous system depressant (CNS depressant) activities of Tryptophan.

Check this interaction

Thalidomide

Moderate

DB01041

Tryptophan may increase the central nervous system depressant (CNS depressant) activities of Thalidomide.

Check this interaction

Zolpidem

Moderate

DB00425

Tryptophan may increase the central nervous system depressant (CNS depressant) activities of Zolpidem.

Check this interaction

Methadone

Unknown severity

DB00333

The risk or severity of adverse effects can be increased when Methadone is combined with Tryptophan.

Check this interaction

Linezolid

Major

DB00601

The risk or severity of serotonin syndrome can be increased when Linezolid is combined with Tryptophan.

Check this interaction

Dicoumarol

Unknown severity

DB00266

The risk or severity of adverse effects can be increased when Tryptophan is combined with Dicoumarol.

Check this interaction

Phenindione

Unknown severity

DB00498

The risk or severity of adverse effects can be increased when Tryptophan is combined with Phenindione.

Check this interaction

Warfarin

Unknown severity

DB00682

The risk or severity of adverse effects can be increased when Tryptophan is combined with Warfarin.

Check this interaction

Phenprocoumon

Unknown severity

DB00946

The risk or severity of adverse effects can be increased when Tryptophan is combined with Phenprocoumon.

Check this interaction

Acenocoumarol

Unknown severity

DB01418

The risk or severity of adverse effects can be increased when Tryptophan is combined with Acenocoumarol.

Check this interaction

4-hydroxycoumarin

Unknown severity

DB03410

The risk or severity of adverse effects can be increased when Tryptophan is combined with 4-hydroxycoumarin.

Check this interaction

Coumarin

Unknown severity

DB04665

The risk or severity of adverse effects can be increased when Tryptophan is combined with Coumarin.

Check this interaction

(R)-warfarin

Unknown severity

DB08496

The risk or severity of adverse effects can be increased when Tryptophan is combined with (R)-warfarin.

Check this interaction

Ethyl biscoumacetate

Unknown severity

DB08794

The risk or severity of adverse effects can be increased when Tryptophan is combined with Ethyl biscoumacetate.

Check this interaction

Fluindione

Unknown severity

DB13136

The risk or severity of adverse effects can be increased when Tryptophan is combined with Fluindione.

Check this interaction

Clorindione

Unknown severity

DB13275

The risk or severity of adverse effects can be increased when Tryptophan is combined with Clorindione.

Check this interaction

Diphenadione

Unknown severity

DB13347

The risk or severity of adverse effects can be increased when Tryptophan is combined with Diphenadione.

Check this interaction

Tioclomarol

Unknown severity

DB13451

The risk or severity of adverse effects can be increased when Tryptophan is combined with Tioclomarol.

Check this interaction

(S)-Warfarin

Unknown severity

DB14055

The risk or severity of adverse effects can be increased when Tryptophan is combined with (S)-Warfarin.

Check this interaction

Mirtazapine

Moderate

DB00370

Tryptophan may increase the serotonergic activities of Mirtazapine.

Check this interaction

Furazolidone

Major

DB00614

The risk or severity of serotonin syndrome and hypomania can be increased when Tryptophan is combined with Furazolidone.

Check this interaction

Procaine

Major

DB00721

The risk or severity of serotonin syndrome and hypomania can be increased when Tryptophan is combined with Procaine.

Check this interaction

Procarbazine

Major

DB01168

The risk or severity of serotonin syndrome and hypomania can be increased when Tryptophan is combined with Procarbazine.

Check this interaction

Rasagiline

Major

DB01367

The risk or severity of serotonin syndrome and hypomania can be increased when Tryptophan is combined with Rasagiline.

Check this interaction

Pargyline

Major

DB01626

The risk or severity of serotonin syndrome and hypomania can be increased when Tryptophan is combined with Pargyline.

Check this interaction

Safinamide

Major

DB06654

The risk or severity of serotonin syndrome and hypomania can be increased when Tryptophan is combined with Safinamide.

Check this interaction

7,8-Dichloro-1,2,3,4-tetrahydroisoquinoline

Major

DB08550

The risk or severity of serotonin syndrome and hypomania can be increased when Tryptophan is combined with 7,8-Dichloro-1,2,3,4-tetrahydroisoquinoline.

Check this interaction

Hydracarbazine

Major

DB09243

The risk or severity of serotonin syndrome and hypomania can be increased when Tryptophan is combined with Hydracarbazine.

Check this interaction

Benmoxin

Major

DB09246

The risk or severity of serotonin syndrome and hypomania can be increased when Tryptophan is combined with Benmoxin.

Check this interaction

Mebanazine

Major

DB09248

The risk or severity of serotonin syndrome and hypomania can be increased when Tryptophan is combined with Mebanazine.

Check this interaction

Octamoxin

Major

DB09249

The risk or severity of serotonin syndrome and hypomania can be increased when Tryptophan is combined with Octamoxin.

Check this interaction

Showing 50 of 703 interactions

Toxicity & overdose

Oral rat LD₅₀: > 16 gm/kg. Investigated as a tumorigen, mutagen, reproductive effector. Symptoms of overdose include agitation, confusion, diarrhea, fever, overactive reflexes, poor coordination, restlessness, shivering, sweating, talking or acting with excitement you cannot control, trembling or shaking, twitching, and vomiting.

How it works

Mechanism of action

A number of important side reactions occur during the catabolism of tryptophan on the pathway to acetoacetate. The first enzyme of the catabolic pathway is an iron porphyrin oxygenase that opens the indole ring. The latter enzyme is highly inducible, its concentration rising almost 10-fold on a diet high in tryptophan. Kynurenine is the first key branch point intermediate in the pathway. Kynurenine undergoes deamniation in a standard transamination reaction yielding kynurenic acid. Kynurenic acid and metabolites have been shown to act as antiexcitotoxics and anticonvulsives. A second side branch reaction produces anthranilic acid plus alanine. Another equivalent of alanine is produced further along the main catabolic pathway, and it is the production of these alanine residues that allows tryptophan to be classified among the glucogenic and ketogenic amino acids. The second important branch point converts kynurenine into 2-amino-3-carboxymuconic semialdehyde, which has two fates. The main flow of carbon elements from this intermediate is to glutarate. An important side reaction in liver is a transamination and several rearrangements to produce limited amounts of nicotinic acid, which leads to production of a small amount of NAD⁺ and NADP⁺.

Pharmacodynamics

Tryptophan is critical for the production of the body's proteins, enzymes and muscle tissue. It is also essential for the production of niacin, the synthesis of the neurotransmitter serotonin and melatonin. Tryptophan supplements can be used as natural relaxants to help relieve insomnia. Tryptophan can also reduce anxiety and depression and has been shown to reduce the intensity of migraine headaches. Other promising indications include the relief of chronic pain, reduction of impulsivity or mania and the treatment of obsessive or compulsive disorders. Tryptophan also appears to help the immune system and can reduce the risk of cardiac spasms. Tryptophan deficiencies may lead to coronary artery spasms. Tryptophan is used as an essential nutrient in infant formulas and intravenous feeding. Tryptophan is marketed as a prescription drug (Tryptan) for those who do not seem to respond well to conventional antidepressants. It may also be used to treat those afflicted with seasonal affective disorder (a winter-onset depression). Tryptopan serves as the precursor for the synthesis of serotonin (5-hydroxytryptamine, 5-HT) and melatonin (N-acetyl-5-methoxytryptamine).

Pharmacokinetics

How the body processes this drug — absorption, distribution, metabolism, and elimination

Metabolism

Hepatic.

Drug targets(3)

Proteins and enzymes this drug interacts with in the body

Indoleamine 2,3-dioxygenase 1

BE0000693

IDO1

binder

Specific functionelectron transfer activity

Cellular location

Cytoplasm, cytosol

General function & pharmacology

Catalyzes the first and rate limiting step of the catabolism of the essential amino acid tryptophan along the kynurenine pathway .
PMID:17671174
Involved in the peripheral immune tolerance, contributing to maintain homeostasis by preventing autoimmunity or immunopathology that would result from uncontrolled and overreacting immune responses .
PMID:25691885
Tryptophan shortage inhibits T lymphocytes division and accumulation of tryptophan catabolites induces T-cell apoptosis and differentiation of regulatory T-cells .
PMID:25691885
Acts as a suppressor of anti-tumor immunity .
PMID:14502282 PMID:23103127 PMID:25157255 PMID:25691885

Limits the growth of intracellular pathogens by depriving tryptophan .
PMID:25691885
Protects the fetus from maternal immune rejection PMID:25691885

Tryptophan--tRNA ligase, cytoplasmic

BE0000228

WARS1

inhibitor

Specific functionATP binding

Cellular location

Cytoplasm

General function & pharmacology

Catalyzes the attachment of tryptophan to tRNA(Trp) in a two-step reaction: tryptophan is first activated by ATP to form Trp-AMP and then transferred to the acceptor end of the tRNA(Trp)

Tryptophan--tRNA ligase, mitochondrial

BE0002311

WARS2

inhibitor

Specific functionATP binding

Cellular location

Mitochondrion matrix

General function & pharmacology

Catalyzes the attachment of tryptophan to tRNA(Trp) in a two-step reaction: tryptophan is first activated by ATP to form Trp-AMP and then transferred to the acceptor end of tRNA(Trp)

Metabolizing enzymes(7)

Enzymes involved in drug metabolism — important for understanding drug interactions

Enzyme activity key

substrate

inhibitor

inducer

WARS2Tryptophan--tRNA ligase, mitochondrial

substrate

inhibitor

TPH1Tryptophan 5-hydroxylase 1

substrate

TPH2Tryptophan 5-hydroxylase 2

substrate

WARS1Tryptophan--tRNA ligase, cytoplasmic

substrate

inhibitor

IDO1Indoleamine 2,3-dioxygenase 1

substrate

TDO2Tryptophan 2,3-dioxygenase

substrate

DDCAromatic-L-amino-acid decarboxylase

substrate

Transporters(2)

Proteins that transport this drug across cell membranes

Monocarboxylate transporter 8

BE0000178

SLC16A2

inhibitor

Specific functionamino acid transmembrane transporter activity

Cellular location

Cell membrane

General function & pharmacology

Specific thyroid hormone transmembrane transporter, that mediates both uptake and efflux of thyroid hormones across the cell membrane independently of pH or a Na(+) gradient. Major substrates are the iodothyronines T3 and T4 and to a lesser extent rT3 and 3,3-diiodothyronine (3,3'-T2) .
PMID:16887882 PMID:18337592 PMID:20628049 PMID:23550058 PMID:26426690 PMID:27805744 PMID:31436139

Acts as an important mediator of thyroid hormone transport, especially T3, through the blood-brain barrier (Probable) PMID:28526555

Monocarboxylate transporter 10

BE0003654

SLC16A10

inhibitor

Specific functionamino acid transmembrane transporter activity

Cellular location

Cell membrane

General function & pharmacology

Sodium- and proton-independent thyroid hormones and aromatic acids transporter .
PMID:11827462 PMID:18337592 PMID:28754537

Mediates both uptake and efflux of 3,5,3'-triiodothyronine (T3) and 3,5,3',5'-tetraiodothyronine (T4) with high affinity, suggesting a role in the homeostasis of thyroid hormone levels .
PMID:18337592
Responsible for low affinity bidirectional transport of the aromatic amino acids, such as phenylalanine, tyrosine, tryptophan and L-3,4-dihydroxyphenylalanine (L-dopa) .
PMID:11827462 PMID:28754537
Plays an important role in homeostasis of aromatic amino acids (By similarity)

Biological pathways(1)

ATC classification(1 code)

ATC N06AX02

Affected organisms(1)

Humans and other mammals

International brands(1)

Experimental properties(5)

Commercial products(256)

Chemical identifiers

CAS, UNII, InChI Key and database cross-references

Show

Linked compound data from DrugBank Open Data (CC BY-NC 4.0)

Tryptophan

DB00150

CAS number

73-22-3

UNII (FDA)

8DUH1N11BX

InChI Key (molecular fingerprint)

QIVBCDIJIAJPQS-VIFPVBQESA-N

Additional database identifiers

Drugs Product Database (DPD)

10238

ChEBI

16828

PubChem Compound

6305

PubChem Substance

46508329

KEGG Compound

C00078

KEGG Drug

D00020

ChemSpider

6066

BindingDB

21974

PharmGKB

PA10323

PDB

TRP

Therapeutic Targets Database

DAP001316

IUPHAR

717

Guide to Pharmacology

717

Wikipedia

Tryptophan

ChEMBL

CHEMBL54976

ZINC

ZINC000000083315

RxCUI

10898

HUGO Gene Nomenclature Committee (HGNC)

HGNC:6059

GenAtlas

INDO

GeneCards

IDO1

GenBank Gene Database

M34455

GenBank Protein Database

306956

Guide to Pharmacology

2829

UniProtKB

P14902

UniProt Accession

I23O1_HUMAN

HUGO Gene Nomenclature Committee (HGNC)

HGNC:12729

GenAtlas

WARS

GeneCards

WARS1

GenBank Gene Database

M77804

GenBank Protein Database

184657

UniProtKB

P23381

UniProt Accession

SYWC_HUMAN

GenBank Gene Database

M14742

GenBank Protein Database

143784

UniProtKB

P00953

UniProt Accession

SYW_GEOSE

HUGO Gene Nomenclature Committee (HGNC)

HGNC:12730

GenAtlas

WARS2

GeneCards

WARS2

GenBank Gene Database

AJ242739

GenBank Protein Database

6572289

UniProtKB

Q9UGM6

UniProt Accession

SYWM_HUMAN

GenBank Gene Database

M14742

GenBank Protein Database

143784

UniProtKB

P00953

UniProt Accession

SYW_GEOSE

HUGO Gene Nomenclature Committee (HGNC)

HGNC:12730

GenAtlas

WARS2

GeneCards

WARS2

GenBank Gene Database

AJ242739

GenBank Protein Database

6572289

UniProtKB

Q9UGM6

UniProt Accession

SYWM_HUMAN

HUGO Gene Nomenclature Committee (HGNC)

HGNC:12008

GenAtlas

TPH1

GeneCards

TPH1

GenBank Gene Database

X52836

GenBank Protein Database

37955

Guide to Pharmacology

1241

UniProtKB

P17752

UniProt Accession

TPH1_HUMAN

HUGO Gene Nomenclature Committee (HGNC)

HGNC:20692

GenAtlas

TPH2

GeneCards

TPH2

GenBank Gene Database

AY098914

GenBank Protein Database

27497159

Guide to Pharmacology

1242

UniProtKB

Q8IWU9

UniProt Accession

TPH2_HUMAN

HUGO Gene Nomenclature Committee (HGNC)

HGNC:12729

GenAtlas

WARS

GeneCards

WARS1

GenBank Gene Database

M77804

GenBank Protein Database

184657

UniProtKB

P23381

UniProt Accession

SYWC_HUMAN

HUGO Gene Nomenclature Committee (HGNC)

HGNC:6059

GenAtlas

INDO

GeneCards

IDO1

GenBank Gene Database

M34455

GenBank Protein Database

306956

Guide to Pharmacology

2829

UniProtKB

P14902

UniProt Accession

I23O1_HUMAN

HUGO Gene Nomenclature Committee (HGNC)

HGNC:11708

GeneCards

TDO2

GenBank Gene Database

U32989

GenBank Protein Database

993046

Guide to Pharmacology

2887

UniProtKB

P48775

UniProt Accession

T23O_HUMAN

HUGO Gene Nomenclature Committee (HGNC)

HGNC:2719

GenAtlas

DDC

GeneCards

DDC

GenBank Gene Database

M76180

GenBank Protein Database

181521

UniProtKB

P20711

UniProt Accession

DDC_HUMAN

HUGO Gene Nomenclature Committee (HGNC)

HGNC:10923

GenAtlas

SLC16A2

GeneCards

SLC16A2

GenBank Gene Database

U05321

GenBank Protein Database

458255

UniProtKB

P36021

UniProt Accession

MOT8_HUMAN

HUGO Gene Nomenclature Committee (HGNC)

HGNC:17027

GeneCards

SLC16A10

GenBank Gene Database

AB057445

GenBank Protein Database

18640047

UniProtKB

Q8TF71

UniProt Accession

MOT10_HUMAN

International reference pricing

15 formulations

Reference pricing from DrugBank. Prices are indicative and may not reflect current UK costs.

From $0.33/capsule

To $1.60/tablet

L-tryptophan 500 mg capsule

$0.33/capsule

Tryptan 250 mg Tablet

$0.40/tablet

Apo-Tryptophan 500 mg Capsule

$0.45/capsule

Apo-Tryptophan 500 mg Tablet

$0.45/tablet

Pms-Tryptophan 500 mg Capsule

$0.45/capsule

Source: DrugBank. Used under CC BY-NC 4.0 academic licence for non-commercial purposes.

Patent information

1 active patent

12390398

United States

Approved 3 May 2016 · Expires 3 May 2036

10y 1m

Source: DrugBank · CC BY-NC 4.0. Patent data sourced from national patent offices. Expiry dates may not reflect extensions, regulatory exclusivity periods, or legal challenges.

DrugBank citations

If you use DrugBank data in your research, please cite the following publications:

Knox C., Wilson M., Klinger C.M., et al

DrugBank 6.

0: the DrugBank Knowledgebase for 2024

Nucleic Acids Res. 2024 Jan 552(D1):D1265-D1275

PMID: 37953279

Wishart D.S., Feunang Y.D., Guo A.C., et al

DrugBank 5.

0: a major update to the DrugBank database for 2018

Nucleic Acids Res. 2017 Nov 846(D1):D1074-D1082

PMID: 29126136

Show earlier publications

Law V., Knox C., Djoumbou Y., et al

DrugBank 4.

0: shedding new light on drug metabolism

Nucleic Acids Res. 2014 Jan 142(1):D1091-7

PMID: 24203711

Knox C., Law V., Jewison T., et al

DrugBank 3.

0: a comprehensive resource for 'omics' research on drugs

Nucleic Acids Res. 2011 Jan39(Database issue):D1035-41

PMID: 21059682

Wishart D.S., Knox C., Guo A.C., et al

DrugBank: a knowledgebase for drugs, drug actions and drug targets.

Nucleic Acids Research

2008 Jan36(Database issue):D901-6

PMID: 18048412

Wishart D.S., Knox C., Guo A.C., et al

DrugBank: a comprehensive resource for in silico drug discovery and exploration.

Nucleic Acids Research

2006 Jan 134(Database issue):D668-72

PMID: 16381955

Source: go.drugbank.comCC BY-NC 4.0

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