Chlorpropamide

Chlorpropamide

Clinical data
Trade names	Diabinese
AHFS/Drugs.com	Monograph
MedlinePlus	a682479
License data	US FDA: Chlorpropamide
Pregnancy category	AU: C US: C (Risk not ruled out)
Routes of administration	Oral
ATC code	A10BB02 (WHO)
Legal status
Legal status	AU: S4 (Prescription only) CA: ℞-only UK: POM (Prescription only) US: ℞-only
Pharmacokinetic data
Bioavailability	>90%
Protein binding	90%
Metabolism	<1%
Biological half-life	36 hours
Excretion	Renal (glomerular filtration → reabsorption → tubular secretion)
Identifiers
IUPAC name 4-chloro-N-(propylcarbamoyl)benzenesulfonamide
CAS Number	94-20-2 Y
PubChem CID	2727
IUPHAR/BPS	6801
DrugBank	DB00672 Y
ChemSpider	2626 Y
UNII	WTM2C3IL2X
KEGG	D00271 Y
ChEBI	CHEBI:3650 Y
ChEMBL	CHEMBL498 Y
ECHA InfoCard	100.002.104
Chemical and physical data
Formula	C10H13ClN2O3S
Molar mass	276.74 g/mol
3D model (Jmol)	Interactive image
Melting point	126 to 130 °C (259 to 266 °F)
SMILES O=S(=O)(c1ccc(Cl)cc1)NC(=O)NCCC
InChI InChI=1S/C10H13ClN2O3S/c1-2-7-12-10(14)13-17(15,16)9-5-3-8(11)4-6-9/h3-6H,2,7H2,1H3,(H2,12,13,14) Y Key:RKWGIWYCVPQPMF-UHFFFAOYSA-N Y

Chlorpropamide is a drug in the sulfonylurea class used to treat diabetes mellitus type 2. It is a long-acting first-generation sulfonylurea. It has more side effects than other sulfonylureas and its use is no longer recommended.

Like other sulfonylureas, chlorpropamide acts to increase the secretion of insulin, so it is only effective in patients who have some pancreatic beta cell function. It can cause relatively long episodes of hypoglycemia; this is one reason why shorter-acting sulfonylureas such as gliclazide or tolbutamide are used instead. The risk of hypoglycemia makes this drug a poor choice for the elderly and patients with mild to moderate hepatic and renal impairment. Chlorpropamide is also used in partial central diabetes insipidus.

Maximal plasma concentrations are reached 3 to 5 hours after quick and nearly complete (>90%) resorption from the gut. Plasma half life is 36 hours; the drug is effective for about 24 hours, longer than other sulfonylureas. A stable plasma level is only reached after three days of continuous application. 90% of the drug are bound to plasma proteins; at least two albumin binding sites exist. More than 99% of chlorpropamide are excreted unchanged via the kidneys. It is first filtrated in the glomeruli, then reabsorbed, and finally secreted into the tubular lumen.

Chlorpropamide and other sulfonylureas encourage weight gain, so they are generally not favored for use in very obese patients. Metformin (Glucophage) is considered a better drug for these patients. Sulfonylureas should be used with caution or generally avoided in patients with hepatic and renal impairment, patients with porphyria, patients who are breastfeeding, patients with ketoacidosis, and elderly patients. Chlorpropamide, while effective in the treatment of diabetics in patients of Chinese descent, should never be used in people of Mongolian descent.