CHLORPROPAMIDE- chlorpropamide tablet
Rx Only
11001198
MARCH 2007
DESCRIPTION
ChlorproPAMIDE is an oral blood-glucose-lowering drug of the sulfonylurea class. ChlorproPAMIDE is a white, crystalline powder that has a slight odor. It is practically insoluble in water, at pH 7.3 (solubility at pH 6 is 2.2 mg/ml). It is soluble in alcohol and moderately soluble in chloroform. Chemically, chlorproPAMIDE is 1-[(p -Chlorophenyl)sulfonyl]-3-propylurea and has the structural formula:
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Molecular formula: C10 H13 CIN2 O3 S Molecular weight: 276.74
Each tablet for oral administration contains 100 mg or 250 mg of chlorproPAMIDE, USP. Inactive ingredients are anhydrous lactose, colloidal silicon dioxide, croscarmellose sodium, docusate sodium and sodium benzoate, hypromellose, microcrystalline cellulose, polacrilin potassium, polyethylene glycol 8000, sodium starch glycolate, stearic acid, and FD&C Blue #1.
CLINICAL PHARMACOLOGY
ChlorproPAMIDE appears to lower the blood glucose acutely by stimulating the release of insulin from the pancreas, an effect dependent upon functioning beta cells in the pancreatic islets. The mechanism by which chlorproPAMIDE lowers blood glucose during long-term administration has not been clearly established. Extra-pancreatic effects may play a part in the mechanism of action of oral sulfonylurea hypoglycemic drugs. While chlorproPAMIDE is a sulfonamide derivative, it is devoid of antibacterial activity.
ChlorproPAMIDE may also prove effective in controlling certain patients who have experienced primary or secondary failure to other sulfonylurea agents.
ChlorproPAMIDE does not interfere with the usual tests to detect albumin in the urine. ChlorproPAMIDE is absorbed rapidly from the gastrointestinal tract. Within one hour after a single oral dose, it is readily detectable in the blood, and the level reaches a maximum within two to four hours. It undergoes metabolism in humans and it is excreted in the urine as unchanged drug and as hydroxylated or hydrolyzed metabolites. The biological half-life of chlorproPAMIDE averages about 36 hours. Within 96 hours, 80 to 90% of a single oral dose is excreted in the urine. However, long-term administration of therapeutic doses does not result in undue accumulation in the blood, since absorption and excretion rates become stabilized in about 5 to 7 days after the initiation of therapy.
ChlorproPAMIDE exerts a hypoglycemic effect in normal humans within one hour, becoming maximal at 3 to 6 hours and persisting for at least 24 hours. The potency of chlorproPAMIDE is approximately six times that of tolbutamide. Some experimental results suggest that its increased duration of action may be the result of slower excretion and absence of significant deactivation.
INDICATIONS AND USAGE
ChlorproPAMIDE is indicated as an adjunct to diet to lower the blood glucose in patients with non-insulin-dependent diabetes mellitus (type ll) whose hyperglycemia cannot be controlled by diet alone.
In initiating treatment for non-insulin-dependent diabetes, diet should be emphasized as the primary form of treatment. Caloric restriction and weight loss are essential in the obese diabetic patient. Proper dietary management alone may be effective in controlling the blood glucose and symptoms of hyperglycemia. The importance of regular physical activity should also be stressed, and cardiovascular risk factors should be identified and corrective measures taken where possible.
If this treatment program fails to reduce symptoms and/or blood glucose, the use of an oral sulfonylurea or insulin should be considered. Use of chlorproPAMIDE must be viewed by both the physician and patient as a treatment in addition to diet, and not as a substitute for diet or as a convenient mechanism for avoiding dietary restraint.
Furthermore, loss of blood glucose control on diet alone may be transient, thus requiring only short-term administration of chlorproPAMIDE.
During maintenance programs, chlorproPAMIDE should be discontinued if satisfactory lowering of blood glucose is no longer achieved. Judgments should be based on regular clinical and laboratory evaluations.
In considering the use of chlorproPAMIDE in asymptomatic patients, it should be recognized that controlling the blood glucose in non-insulin-dependent diabetes has not been definitely established to be effective in preventing the long-term cardiovascular or neural complications of diabetes.
