Systematic (IUPAC) name
ethyl 2-(4-chlorophenoxy)-2-methylpropanoate
Clinical data
AHFS/ Micromedex Detailed Consumer Information
Pregnancy cat. B1(AU) C(US)
Legal status -only (US)
Routes Oral
Pharmacokinetic data
Protein binding Variable, 92–97% at therapeutic concentrations
Metabolism Hydrolyzed to clofibric acid; hepatic glucuronidation
Half-life Highly variable; average 18–22 hours. Prolonged in renal failure
Excretion Renal, 95 to 99%
CAS number 637-07-0
ATC code C10AB01
PubChem CID 2796
DrugBank APRD00879
ChemSpider 2694 YesY
KEGG D00279 YesY
Chemical data
Formula C12H15ClO3 
Mol. mass 242.698 g/mol
SMILES eMolecules & PubChem
Physical data
Boiling point 148 °C (298 °F)
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Clofibrate (tradename Atromid-S) is a fibrate. It is a lipid lowering agent used for controlling the high cholesterol and triacylglyceride level in the blood. It increases lipoprotein lipase activity to promote the conversion of VLDL to LDL, and hence reduce the level of VLDL. It is proved that it can increase the level of HDL as well.

It can induce SIADH, syndrome of inappropriate secretion of antidiuretic hormone ADH (vasopressin).

The World Health Organization Cooperative Trial on Primary Prevention of Ischaemic Heart Disease using clofibrate to lower serum cholesterol observed that there was excess mortality in the clofibrate-treated group despite successful cholesterol lowering (47% more deaths during treatment with clofibrate and 5% after treatment with clofibrate) than the non-treated high cholesterol group. These deaths were due to a wide variety of causes other than heart disease, and remain "unexplained".[1]


  1. ^ "WHO cooperative trial on primary prevention of ischaemic heart disease with clofibrate to lower serum cholesterol: final mortality follow-up. Report of the Committee of Principal Investigators". Lancet 2 (8403): 600–4. September 1984. PMID 6147641.