L-Phenylalanine 25mg capsules
Requires a prescription from a doctor or prescriber
Phenylalanine is an essential aromatic amino acid that is a precursor of melanin, [dopamine], [noradrenalin] (norepinephrine), and [thyroxine].
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Safety monitoring data
Yellow Card reports
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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
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1 branded products available
Therapeutically similar medicines
Similarity is based on WHO Anatomical Therapeutic Chemical (ATC) classification and on a factual NHS dm+d therapeutic-grouping code prefix. Source data: NHS dm+d via TRUD (OGL v3.0), WHO ATC/DDD Index.
NHS prescribing volume and spending trends
Check stock at pharmacies and supply information
Pharmacy stock checkers
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Supply & safety information
Official UK regulator monitoring and safety alerts
Pharmacy links redirect to the retailer's own search and do not represent real-time stock levels. Shortage and safety information sourced from MHRA drug safety updates (gov.uk, Crown Copyright under OGL v3.0).
Codes for healthcare professionals and prescribing systems
These codes are used by healthcare IT systems and prescribers to identify this medicine.
NHS UK identifiers
SNOMED CT and dm+d codes from NHS TRUD (Technology Reference data Update Distribution), licensed under the Open Government Licence v3.0. BNF code shown is the factual mapping value distributed by NHS Business Services Authority (NHSBSA) in the dm+d supplementary file under OGL v3.0; it is not affiliated with, nor licensed from, the publishers of the British National Formulary.
Active and completed clinical studies from ClinicalTrials.gov
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.
Academic studies and reviews for this medicine's active substance
Showing the 50 most relevant studies.
Reviews & meta-analyses: 4 · 1963–2025
Showing the 50 most relevant studies, sorted by most relevant.
J. Chin, Stephen W. Santoro, Andrew B. Martin, et al.
Journal of the American Chemical Society, 2002
L. Zwelling, S. Michaels, H. Schwartz, et al.
Cancer research, 1981
Tak H. Lee, C. Horton, U. Kyan-Aung, et al.
Clinical science, 1989
W. Fishman, S. Green, N. I. Inglis
Nature, 1963
James C. KauerS, S. Erickson-Viitanen, H. Wolfe, et al.
The Journal of biological chemistry, 1986
Min Qiu, Jie Jiang, Wankui Jiang, et al.
Biotechnology advances, 2024
- Phenylalanine
- Metabolic Engineering
- Bacteria
A. Liou, Y. Sei, Xilin Zhao, et al.
American journal of physiology. Gastrointestinal and liver physiology, 2011
G. Canellos, S. Pocock, S. Taylor, et al.
Cancer, 1976
F. Wang, Chuanliang Feng
Angewandte Chemie, 2018
G. Bolwell, J. Bell, C. Cramer, et al.
European journal of biochemistry, 1985
Sources: aggregated from Europe PMC (EMBL-EBI), OpenAlex, Crossref, PubMed and other open scholarly databases. Retracted articles are excluded. Study information is provided for research purposes and does not constitute medical advice.
Pharmacology and chemical data from DrugBank
Key facts
Drug status
Approved
Major interactions
None known
Half-life
Not available
Mechanism
The supposed antidepressant effects of L-phenylalanine may be due to its role as…
Food interactions
None known
Human targets
7 targets
Data: DrugBank · CC BY-NC 4.0
Pharmacokinetics at a glance
Absorption
Metabolism
Pharmacokinetic data: DrugBank · CC BY-NC 4.0
Known interactions with other medications. Always consult a healthcare professional.
Showing 50 of 494 interactions
How the body processes this drug — absorption, distribution, metabolism, and elimination
Proteins and enzymes this drug interacts with in the body
Positively regulates the regression of retinal hyaloid vessels during postnatal development (By similarity)
Has much lower affinity and transaminase activity towards phenylalanine
PMID:10391915 PMID:11311135 PMID:11847106 PMID:12716892 PMID:15081149 PMID:15918515 PMID:29355479 PMID:33298890 PMID:34848541
Has relatively symmetrical selectivities but strongly asymmetrical substrate affinities at both the intracellular and extracellular sides of the transporter .
PMID:11847106
This asymmetry allows SLC7A8 to regulate intracellular amino acid pools (mM concentrations) by exchange with external amino acids (uM concentration range), equilibrating the relative concentrations of different amino acids across the plasma membrane instead of mediating their net uptake .
PMID:10391915 PMID:11847106
May play an essential role in the reabsorption of neutral amino acids from the epithelial cells to the bloodstream in the kidney .
PMID:12716892
Involved in the uptake of methylmercury (MeHg) when administered as the L-cysteine or D,L-homocysteine complexes, and hence plays a role in metal ion homeostasis and toxicity .
PMID:12117417
Involved in the cellular activity of small molecular weight nitrosothiols, via the stereoselective transport of L-nitrosocysteine (L-CNSO) across the transmembrane .
PMID:15769744
Imports the thyroid hormone diiodothyronine (T2) and to a smaller extent triiodothyronine (T3) but not rT 3 or thyroxine (T4) (By similarity). Mediates the uptake of L-DOPA (By similarity).
May participate in auditory function (By similarity)
Proteins that transport this drug across cell membranes
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)
Chemical identifiers
CAS, UNII, InChI Key and database cross-references
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Chemical identifiers
CAS, UNII, InChI Key and database cross-references
Linked compound data from DrugBank Open Data (CC BY-NC 4.0)
Phenylalanine
Matched from: L-Phenylalanine
Additional database identifiers
Drugs Product Database (DPD)
942
Drugs Product Database (DPD)
10223
Drugs Product Database (DPD)
750
ChemSpider
5910
BindingDB
18073
PDB
PHE
Guide to Pharmacology
3313
ZINC
ZINC000000105196
HUGO Gene Nomenclature Committee (HGNC)
HGNC:11782
GenAtlas
TH
GeneCards
TH
GenBank Gene Database
Y00414
GenBank Protein Database
37127
UniProt Accession
TY3H_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:11573
GenAtlas
TAT
GeneCards
TAT
GenBank Gene Database
X52520
GenBank Protein Database
36713
UniProt Accession
ATTY_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:11066
GenAtlas
SLC7A8
GeneCards
SLC7A8
GenBank Gene Database
AF171669
GenBank Protein Database
6642960
UniProt Accession
LAT2_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:3592
GenAtlas
FARSLA
GeneCards
FARSA
GenBank Gene Database
U07424
GenBank Protein Database
2102679
UniProt Accession
SYFA_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:8582
GenAtlas
PAH
GeneCards
PAH
GenBank Gene Database
K03020
GenBank Protein Database
189937
Guide to Pharmacology
1240
UniProt Accession
PH4H_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:21062
GenAtlas
FARS2
GeneCards
FARS2
GenBank Gene Database
AF097441
GenBank Protein Database
3983103
UniProt Accession
SYFM_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:17800
GenAtlas
FARSLB
GeneCards
FARSB
GenBank Gene Database
D84430
GenBank Protein Database
7768938
UniProt Accession
SYFB_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:17027
GeneCards
SLC16A10
GenBank Gene Database
AB057445
GenBank Protein Database
18640047
UniProt Accession
MOT10_HUMAN
DrugBank citations
If you use DrugBank data in your research, please cite the following publications:
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Structured knowledge from the free knowledge base
Linked open data from Wikidata (Q106345467), a free and open knowledge base operated by the Wikimedia Foundation. Data is available under the Creative Commons CC0 1.0 Public Domain Dedication.