Phenazone

Phenazone

Clinical data
ATC code	N02BB01 (WHO) S02DA03 (WHO)
Pharmacokinetic data
Biological half-life	12 hours
Identifiers
IUPAC name 1,2-Dihydro-1,5-dimethyl-2-phenyl-3H-pyrazol-3-one
Synonyms	analgesine, antipyrine
CAS Number	60-80-0 Y
PubChem (CID)	2206
DrugBank	DB01435 Y
ChemSpider	2121 Y
UNII	T3CHA1B51H Y
KEGG	D01776 Y
ChEBI	CHEBI:31225 Y
ChEMBL	CHEMBL277474 Y
ECHA InfoCard	100.000.442
Chemical and physical data
Formula	C11H12N2O
Molar mass	188.2258g/mol
3D model (Jmol)	Interactive image
SMILES O=C2\C=C(/N(N2c1ccccc1)C)C
InChI InChI=1S/C11H12N2O/c1-9-8-11(14)13(12(9)2)10-6-4-3-5-7-10/h3-8H,1-2H3 Y Key:VEQOALNAAJBPNY-UHFFFAOYSA-N Y
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Phenazone (INN and BAN; also known as phenazon, antipyrine (USAN), or analgesine) is an analgesic, a non-steroidal anti-inflammatory drug and an antipyretic. It was first synthesized by Ludwig Knorr in 1887.^{[1][2]:26–27} Phenazone is synthesized^[3] by condensation of phenylhydrazine and ethyl acetoacetate under basic conditions and methylation of the resulting intermediate compound 1-phenyl-3-methylpyrazolone^[4] with dimethyl sulfate or methyl iodide. It crystallizes in needles which melt at 156 °C. Potassium permanganate oxidizes it to pyridazine tetracarboxylic acid. Phenazone has an elimination half life of about 12 hours.^[5] Indication: Used to relieve pain and fever. Antipyrine is often used in testing the effects of other drugs or diseases on drug-metabolizing enzymes in the liver.^[6]

Adverse effects

Possible adverse effects include:

• Allergy to pyrazolones
• Nausea
• Agranulocytosis
• Hepatotoxicity

See also

• Propyphenazone
• A/B Otic Drops, ear drops combined with benzocaine to relieve pain and remove cerumen

References