Fenoprofen

Fenoprofen
Clinical data
Trade names	Nalfon
AHFS/Drugs.com	Monograph
MedlinePlus	a681026
Pregnancy; category	C;
Routes of; administration	By mouth
ATC code	M01AE04 (WHO) ;
Legal status
Legal status	UK: POM (Prescription only); US: WARNINGRx-only;
Pharmacokinetic data
Metabolism	Major urinary metabolites are fenoprofen glucuronide and 4′-hydroxyfenoprofen glucuronide.
Elimination half-life	3 hours
Excretion	Renal (~90%)
Identifiers
	IUPAC name 2-(3-phenoxyphenyl)propanoic acid;
CAS Number	29679-58-1 ;
PubChem CID	3342;
IUPHAR/BPS	4820;
DrugBank	DB00573 ;
ChemSpider	3225 ;
UNII	RA33EAC7KY;
KEGG	D02350 ;
ChEBI	CHEBI:5004 ;
ChEMBL	ChEMBL1297 ;
CompTox Dashboard (EPA)	DTXSID9023045 ;
ECHA InfoCard	100.046.213 100.045.231, 100.046.213
Chemical and physical data
Formula	C15H14O3
Molar mass	242.274 g·mol−1
3D model (JSmol)	Interactive image;
	SMILES O=C(O)C(c2cc(Oc1ccccc1)ccc2)C;
	InChI InChI=1S/C15H14O3/c1-11(15(16)17)12-6-5-9-14(10-12)18-13-7-3-2-4-8-13/h2-11H,1H3,(H,16,17) ; Key:RDJGLLICXDHJDY-UHFFFAOYSA-N ;
	(verify)

Fenoprofen, sold under the brand name Nalfon among others, is a nonsteroidal anti-inflammatory drug (NSAID). Fenoprofen calcium is used for symptomatic relief for rheumatoid arthritis, osteoarthritis, and mild to moderate pain. It has also been used to treat postoperative pain.^[2] It is available as a generic medication.^[3]^[4]

Pharmacology

Decreases inflammation, pain, and fever, probably through inhibition of cyclooxygenase (COX-2 inhibitor) activity and prostaglandin synthesis.

Chirality and biological activity

Fenoprofen is chiral drug with one stereogenic center and exists as chiral twins. (S)-enantiomer has the desired pharmacological action where as the (R)-isomer is less active. It is observed that there is stereoselective bioconversion of the (R)- to (S)-fenoprofen. This stereoselective conversion is called chiral inversion.^[5]^[6]

Contraindications

History of significantly impaired renal function; patients with known hypersensitivity to any component of the product; patients who have experienced asthma, urticaria, or allergic-type reactions after taking aspirin or other NSAIDs; treatment of perioperative pain in the setting of coronary artery bypass graft (CABG) surgery.

Adverse effects

In October 2020, the U.S. Food and Drug Administration (FDA) required the drug label to be updated for all nonsteroidal anti-inflammatory medications to describe the risk of kidney problems in unborn babies that result in low amniotic fluid.^[7]^[8] They recommend avoiding NSAIDs in pregnant women at 20 weeks or later in pregnancy.^[7]^[8]

Drug interactions

Aminoglycosides (e.g. gentamicin): Plasma aminoglycoside levels may be elevated.
Angiotensin-converting enzyme (ACE) inhibitors: Antihypertensive effect of ACE inhibitors may be diminished.
Anticoagulants: Coadministration may prolong prothrombin time.
Aspirin: Fenoprofen Cl may be increased; coadministration is not recommended.
Diuretics: Patients treated with fenoprofen may be resistant to the effects of loop diuretics and thiazides.
Hydantoins, sulfonamides, sulfonylureas: Fenoprofen may displace these drugs from their binding site.
Lithium: Renal Cl of lithium may be reduced and plasma levels may be elevated, which may increase the risk of lithium toxicity.
Methotrexate: May increase methotrexate levels.
Phenobarbital: May decrease fenoprofen t_1⁄2. Dosage adjustments of fenoprofen may be required if phenobarbital is added or withdrawn.
SSRIs (e.g. fluoxetine, citalopram): The risk of GI effects may be increased.

Laboratory test interactions

False elevation in free and total serum T 3 as measured by Amerlex-M kit.^{[medical citation needed]}

Brand names

UK – Fenopron (Typharm Limited)

References

^ "FDA-sourced list of all drugs with black box warnings (Use Download Full Results and View Query links.)". nctr-crs.fda.gov. FDA. Retrieved 22 October 2023.
^ Traa MX, Derry S, Moore RA (February 2011). "Single dose oral fenoprofen for acute postoperative pain in adults". The Cochrane Database of Systematic Reviews. 2011 (2): CD007556. doi:10.1002/14651858.CD007556.pub2. PMC 4171001. PMID 21328296.
^ "2022 First Generic Drug Approvals". U.S. Food and Drug Administration (FDA). 3 March 2023. Archived from the original on 30 June 2023. Retrieved 30 June 2023.
^ "Competitive Generic Therapy Approvals". U.S. Food and Drug Administration (FDA). 29 June 2023. Archived from the original on 29 June 2023. Retrieved 29 June 2023.
^ Rubin A, Knadler MP, Ho PP, Bechtol LD, Wolen RL (January 1985). "Stereoselective inversion of (R)-fenoprofen to (S)-fenoprofen in humans". Journal of Pharmaceutical Sciences. 74 (1): 82–84. doi:10.1002/jps.2600740122. PMID 3920382.
^ Caldwell J, Hutt AJ, Fournel-Gigleux S (January 1988). "The metabolic chiral inversion and dispositional enantioselectivity of the 2-arylpropionic acids and their biological consequences". Biochemical Pharmacology. 37 (1): 105–114. doi:10.1016/0006-2952(88)90762-9. PMID 3276314.
^ ^a ^b "FDA Warns that Using a Type of Pain and Fever Medication in Second Half of Pregnancy Could Lead to Complications". U.S. Food and Drug Administration (FDA) (Press release). 15 October 2020. Retrieved 15 October 2020. This article incorporates text from this source, which is in the public domain.
^ ^a ^b "NSAIDs may cause rare kidney problems in unborn babies". U.S. Food and Drug Administration. 21 July 2017. Retrieved 15 October 2020. This article incorporates text from this source, which is in the public domain.