Mefenamic acid 500mg tablets
Requires a prescription from a doctor or prescriber
A non-steroidal anti-inflammatory agent with analgesic, anti-inflammatory, and antipyretic properties.
Official documents, adverse reaction reporting, and safety monitoring
Report a side effect
Submit a Yellow Card report to the MHRA
Official medicine documents
Safety monitoring data
Yellow Card reports
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 Mefenamic acid
Browse all iDAP reports
Interactive Drug Analysis Profiles for all medicines
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
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 Mefenamic acid
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.
21 branded products available
Part of the Ponstan brand family (generic: Mefenamic acid)
MHRA licensed products
View all licensed products for Mefenamic acid on the MHRA register
Ponstan Forte 500mg tablets
Mefenamic acid 500mg tablets
Mefenamic acid 500mg tablets
Mefenamic acid 500mg tablets
Mefenamic acid 500mg tablets
Mefenamic acid 500mg tablets
Mefenamic acid 500mg tablets
Mefenamic acid 500mg tablets
Mefenamic acid 500mg tablets
Mefenamic acid 500mg tablets
This is the NHS Drug Tariff indicative price used for reimbursement purposes. It may not reflect the price paid by patients or pharmacies.
View full Drug TariffSource: NHS Drug Tariff via NHSBSA. Derived from dm+d VMPP (Virtual Medicinal Product Pack) pricing data. Contains public sector information licensed under the Open Government Licence v3.0.
WHO defined daily dose (DDD)
1 gram
Not a recommended dose. The DDD is the assumed average maintenance dose per day for a drug used for its main indication in adults. It is a statistical measure used for research and comparison purposes only.
Source: WHO Collaborating Centre for Drug Statistics Methodology, distributed via NHS dm+d BNF mapping files. Contains public sector information licensed under the Open Government Licence v3.0.
Therapeutically similar medicines
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
Clinical guidelines and formulary information
British National Formulary
Mefenamic acid
Source: British National Formulary, NICE. Joint Formulary Committee. Contains public sector information licensed under the Open Government Licence v3.0.
Check stock at pharmacies and supply information
Pharmacy stock checkers
Search for this medicine at major UK pharmacy chains. These links open the retailer's own website — results depend on their current online catalogue.
Supply & product information
Official product databases and supply status monitoring
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
These codes are used by healthcare IT systems and prescribers to identify this medicine.
NHS UK identifiers
Browse tools
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
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
Key facts
Drug status
Approved
Major interactions
159 found
Half-life
2 hours
Mechanism
Mefenamic acid binds the prostaglandin synthetase receptors COX-1 and COX-2, inh…
Food interactions
2 warnings
Human targets
2 targets
Data: DrugBank · CC BY-NC 4.0
Pharmacokinetics at a glance
Absorption
Half-life
2 hours
Protein binding
90%
Volume of distribution
1.06 L/kg
Metabolism
Elimination
20%
Clearance
21.23 L/h
Pharmacokinetic data: DrugBank · CC BY-NC 4.0
Known interactions with other medications. Always consult a healthcare professional.
Showing 50 of 1708 interactions
How the body processes this drug — absorption, distribution, metabolism, and elimination
Proteins and enzymes this drug interacts with in the body
PMID:11939906 PMID:16373578 PMID:19540099 PMID:22942274 PMID:26859324 PMID:27226593 PMID:7592599 PMID:7947975 PMID:9261177
The cyclooxygenase activity oxygenates AA to the hydroperoxy endoperoxide prostaglandin G2 (PGG2), and the peroxidase activity reduces PGG2 to the hydroxy endoperoxide prostaglandin H2 (PGH2), the precursor of all 2-series prostaglandins and thromboxanes .
PMID:16373578 PMID:22942274 PMID:26859324 PMID:27226593 PMID:7592599 PMID:7947975 PMID:9261177
This complex transformation is initiated by abstraction of hydrogen at carbon 13 (with S-stereochemistry), followed by insertion of molecular O2 to form the endoperoxide bridge between carbon 9 and 11 that defines prostaglandins. The insertion of a second molecule of O2 (bis-oxygenase activity) yields a hydroperoxy group in PGG2 that is then reduced to PGH2 by two electrons .
PMID:16373578 PMID:22942274 PMID:26859324 PMID:27226593 PMID:7592599 PMID:7947975 PMID:9261177
Similarly catalyzes successive cyclooxygenation and peroxidation of dihomo-gamma-linoleate (DGLA, C20:3(n-6)) and eicosapentaenoate (EPA, C20:5(n-3)) to corresponding PGH1 and PGH3, the precursors of 1- and 3-series prostaglandins .
PMID:11939906 PMID:19540099
In an alternative pathway of prostanoid biosynthesis, converts 2-arachidonoyl lysophopholipids to prostanoid lysophopholipids, which are then hydrolyzed by intracellular phospholipases to release free prostanoids .
PMID:27642067
Metabolizes 2-arachidonoyl glycerol yielding the glyceryl ester of PGH2, a process that can contribute to pain response .
PMID:22942274
Generates lipid mediators from n-3 and n-6 polyunsaturated fatty acids (PUFAs) via a lipoxygenase-type mechanism. Oxygenates PUFAs to hydroperoxy compounds and then reduces them to corresponding alcohols .
PMID:11034610 PMID:11192938 PMID:9048568 PMID:9261177
Plays a role in the generation of resolution phase interaction products (resolvins) during both sterile and infectious inflammation .
PMID:12391014
Metabolizes docosahexaenoate (DHA, C22:6(n-3)) to 17R-HDHA, a precursor of the D-series resolvins (RvDs) .
PMID:12391014
As a component of the biosynthetic pathway of E-series resolvins (RvEs), converts eicosapentaenoate (EPA, C20:5(n-3)) primarily to 18S-HEPE that is further metabolized by ALOX5 and LTA4H to generate 18S-RvE1 and 18S-RvE2 .
PMID:21206090
In vascular endothelial cells, converts docosapentaenoate (DPA, C22:5(n-3)) to 13R-HDPA, a precursor for 13-series resolvins (RvTs) shown to activate macrophage phagocytosis during bacterial infection .
PMID:26236990
In activated leukocytes, contributes to oxygenation of hydroxyeicosatetraenoates (HETE) to diHETES (5,15-diHETE and 5,11-diHETE) .
PMID:22068350 PMID:26282205
Can also use linoleate (LA, (9Z,12Z)-octadecadienoate, C18:2(n-6)) as substrate and produce hydroxyoctadecadienoates (HODEs) in a regio- and stereospecific manner, being (9R)-HODE ((9R)-hydroxy-(10E,12Z)-octadecadienoate) and (13S)-HODE ((13S)-hydroxy-(9Z,11E)-octadecadienoate) its major products (By similarity).
During neuroinflammation, plays a role in neuronal secretion of specialized preresolving mediators (SPMs) 15R-lipoxin A4 that regulates phagocytic microglia (By similarity)
The insertion of a second molecule of O2 (bis-oxygenase activity) yields a hydroperoxy group in PGG2 that is then reduced to PGH2 by two electrons .
PMID:7947975
Involved in the constitutive production of prostanoids in particular in the stomach and platelets. In gastric epithelial cells, it is a key step in the generation of prostaglandins, such as prostaglandin E2 (PGE2), which plays an important role in cytoprotection. In platelets, it is involved in the generation of thromboxane A2 (TXA2), which promotes platelet activation and aggregation, vasoconstriction and proliferation of vascular smooth muscle cells (Probable).
Can also use linoleate (LA, (9Z,12Z)-octadecadienoate, C18:2(n-6)) as substrate and produce hydroxyoctadecadienoates (HODEs) in a regio- and stereospecific manner, being (9R)-HODE ((9R)-hydroxy-(10E,12Z)-octadecadienoate) and (13S)-HODE ((13S)-hydroxy-(9Z,11E)-octadecadienoate) its major products (By similarity)
Enzymes involved in drug metabolism — important for understanding drug interactions
Proteins that carry this drug through the body
PMID:19021548
Major calcium and magnesium transporter in plasma, binds approximately 45% of circulating calcium and magnesium in plasma (By similarity).
Potentially has more than two calcium-binding sites and might additionally bind calcium in a non-specific manner (By similarity). The shared binding site between zinc and calcium at residue Asp-273 suggests a crosstalk between zinc and calcium transport in the blood (By similarity). The rank order of affinity is zinc > calcium > magnesium (By similarity).
Binds to the bacterial siderophore enterobactin and inhibits enterobactin-mediated iron uptake of E.coli from ferric transferrin, and may thereby limit the utilization of iron and growth of enteric bacteria such as E.coli .
PMID:6234017
Does not prevent iron uptake by the bacterial siderophore aerobactin PMID:6234017
ATC M01AG01
Chemical identifiers
CAS, UNII, InChI Key and database cross-references
Show
Chemical identifiers
CAS, UNII, InChI Key and database cross-references
Linked compound data from DrugBank Open Data (CC BY-NC 4.0)
Mefenamic acid
Additional database identifiers
Drugs Product Database (DPD)
10002
ChemSpider
3904
BindingDB
50134036
PDB
ID8
Guide to Pharmacology
2593
ZINC
ZINC000000020241
HUGO Gene Nomenclature Committee (HGNC)
HGNC:9605
GenAtlas
PTGS2
GeneCards
PTGS2
GenBank Gene Database
L15326
GenBank Protein Database
291988
Guide to Pharmacology
1376
UniProt Accession
PGH2_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:9604
GenAtlas
PTGS1
GeneCards
PTGS1
GenBank Gene Database
M31822
GenBank Protein Database
387018
Guide to Pharmacology
1375
UniProt Accession
PGH1_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:2623
GenAtlas
CYP2C9
GeneCards
CYP2C9
GenBank Gene Database
AY341248
Guide to Pharmacology
1326
UniProt Accession
CP2C9_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:2596
GenAtlas
CYP1A2
GeneCards
CYP1A2
GenBank Gene Database
Z00036
Guide to Pharmacology
1319
UniProt Accession
CP1A2_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:12541
GeneCards
UGT1A9
GenBank Gene Database
S55985
GenBank Protein Database
7690346
UniProt Accession
UD19_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:12554
GeneCards
UGT2B7
GenBank Gene Database
J05428
GenBank Protein Database
340080
UniProt Accession
UD2B7_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:2622
GenAtlas
CYP2C8
GeneCards
CYP2C8
GenBank Gene Database
M17397
Guide to Pharmacology
1325
UniProt Accession
CP2C8_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:399
GenAtlas
ALB
GeneCards
ALB
GenBank Gene Database
V00494
GenBank Protein Database
28590
UniProt Accession
ALBU_HUMAN
International reference pricing
Reference pricing from DrugBank. Prices are indicative and may not reflect current UK costs.
Source: DrugBank. Used under CC BY-NC 4.0 academic licence for non-commercial purposes.
DrugBank citations
If you use DrugBank data in your research, please cite the following publications: