"April 11, 2013 -- A new oral diabetes drug is expected to arrive on pharmacy shelves in the U.S. this week.
Many people predict that Invokana (canagliflozin), approved by the FDA in March, will be a brisk seller. That's partly because i"...
Special Warning on Increased Risk of Cardiovascular Mortality
The administration of oral hypoglycemic drugs has been reported to be associated with increased cardiovascular mortality as compared to treatment with diet alone or diet plus insulin. This warning is based on the study conducted by the University Group Diabetes Program (UGDP), a long-term prospective clinical trial designed to evaluate the effectiveness of glucose-lowering drugs in preventing or delaying vascular complications in patients with non-insulin-dependent diabetes. The study involved 823 patients who were randomly assigned to one of four treatment groups (Diabetes, 19 [supp. 2]:747-830,1970).
UGDP reported that patients treated for 5 to 8 years with diet plus a fixed dose of tolbutamide (1.5 grams per day) had a rate of cardiovascular mortality approximately 2V2 times that of patients treated with diet alone. A significant increase in total mortality was not observed, but the use of tolbutamide was discontinued based on the increase in cardiovascular mortality, thus limiting the opportunity for the study to show an increase in over-all mortality. Despite controversy regarding the interpretation of these results, the findings of the UGDP study provide an adequate basis for this warning. The patient should be informed of the potential risks and advantages of DIABINESE (chlorpropamide) and of alternative modes of therapy.
Although only one drug in the sulfonylurea class (tolbutamide) was included in this study, it is prudent from a safety standpoint to consider that this warning may also apply to other oral hypoglycemic drugs in this class, in view of their close similarities in mode of action and chemical structure.
Macrovascular Outcomes: There have been no clinical studies establishing conclusive evidence of macrovascular risk reduction with DIABINESE (chlorpropamide) or any other anti-diabetic drug.
Hypoglycemia: All sulfonylurea drugs including chlorpropamide are capable of producing severe hypoglycemia, which may result in coma, and may require hospitalization. Patients experiencing hypoglycemia should be managed with appropriate glucose therapy and be monitored for a minimum of 24 to 48 hours (see OVERDOSAGE section). Proper patient selection, dosage, and instructions are important to avoid hypoglycemic episodes. Regular, timely carbohydrate intake is important to avoid hypoglycemic events occurring when a meal is delayed or insufficient food is eaten or carbohydrate intake is unbalanced. Renal or hepatic insufficiency may affect the disposition of DIABINESE (chlorpropamide) and may also diminish gluconeogenic capacity, both of which increase the risk of serious hypoglycemic reactions. Elderly, debilitated or malnourished patients, and those with adrenal or pituitary insufficiency are particularly susceptible to the hypoglycemic action of glucose-lowering drugs. Hypoglycemia may be difficult to recognize in the elderly, and in people who are taking beta-adrenergic blocking drugs. Hypoglycemia is more likely to occur when caloric intake is deficient, after severe or prolonged exercise, when alcohol is ingested, or when more than one glucose-lowering drug is used.
Because of the long half-life of chlorpropamide, patients who become hypoglycemic during therapy require careful supervision of the dose and frequent feedings for at least 3 to 5 days. Hospitalization and intravenous glucose may be necessary.
Loss of control of blood glucose: When a patient stabilized on any diabetic regimen is exposed to stress such as fever, trauma, infection, or surgery, a loss of control may occur. At such times, it may be necessary to discontinue DIABINESE (chlorpropamide) and administer insulin.
The effectiveness of any oral hypoglycemic drug, including DIABINESE (chlorpropamide) , in lowering blood glucose to a desired level decreases in many patients over a period of time, which may be due to progression of the severity of the diabetes or to diminished responsiveness to the drug. This phenomenon is known as secondary failure, to distinguish it from primary failure in which the drug is ineffective in an individual patient when first given. Adequate adjustment of dose and adherence to diet should be assessed before classifying a patient as a secondary failure.
Hemolytic Anemia: Treatment of patients with glucose 6-phosphate dehydrogenase (G6PD) deficiency with sulfonylurea agents can lead to hemolytic anemia. Because DIABINESE (chlorpropamide) belongs to the class of sulfonylurea agents, caution should be used in patients with G6PD deficiency and a non-sulfonylurea alternative should be considered. In post marketing reports, hemolytic anemia has also been reported in patients who did not have known G6PD deficiency.
The safety and effectiveness of DIABINESE (chlorpropamide) in patients aged 65 and over has not been properly evaluated in clinical studies. Adverse event reporting suggests that elderly patients may be more prone to developing hypoglycemia and/or hyponatremia when using DIABINESE (chlorpropamide) . Although the underlying mechanisms are unknown, abnormal renal function, drug interaction and poor nutrition appear to contribute to these events.
Carcinogenesis, Mutagenesis, Impairment of Fertility
Studies with DIABINESE (chlorpropamide) have not been conducted to evaluate carcinogenic or mutagenic potential.
Rats treated with continuous DIABINESE (chlorpropamide) therapy for 6 to 12 months showed varying degrees of suppression of spermatogenesis at a dose level of 250 mg/kg (five times the human dose based on body surface area). The extent of suppression seemed to follow that of growth retardation associated with chronic administration of high-dose DIABINESE in rats. The human dose of chlorpropamide is 500 mg/day (300 mg/M2). Six- and 12-month toxicity work in the dog and rat, respectively, indicates the 150 mg/kg is well tolerated. Therefore, the safety margins based upon body-surf ace-area comparisons are three times human exposure in the rat and 10 times human exposure in the dog.
Pregnancy Category C. Animal reproductive studies have not been conducted with DIABINESE (chlorpropamide) . It is also not known whether DIABINESE (chlorpropamide) can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. DIABINESE (chlorpropamide) should be given to a pregnant woman only if the potential benefits justify the potential risk to the patient and fetus.
Because data suggest that abnormal blood glucose levels during pregnancy are associated with a higher incidence of congenital abnormalities, many experts recommend that insulin be used during pregnancy to maintain blood glucose levels as close to normal as possible.
Prolonged severe hypoglycemia (4 to 10 days) has been reported in neonates born to mothers who were receiving a sulfonylurea drug at the time of delivery. This has been reported more frequently with the use of agents with prolonged half-lives. If DIABINESE (chlorpropamide) is used during pregnancy, it should be discontinued at least one month before the expected delivery date and other therapies instituted to maintain blood glucose levels as close to normal as possible.
An analysis of a composite of two samples of human breast milk, each taken five hours after ingestion of 500 mg of chlorpropamide by a patient, revealed a concentration of 5 mcg/mL. For reference, the normal peak blood level of chlorpropamide after a single 250 mg dose is 30 mcg/mL. Therefore, it is not recommended that a woman breast feed while taking this medication.
Use in Children
Safety and effectiveness in children have not been established.
Ability to Drive and Use Machines
The effect of DIABINESE (chlorpropamide) on the ability to drive or operate machinery has not been studied. However, there is no evidence to suggest that DIABINESE (chlorpropamide) may affect these abilities. Patients should be aware of the symptoms of hypoglycemia and take caution while driving and operating machinery.
Last reviewed on RxList: 3/25/2011
This monograph has been modified to include the generic and brand name in many instances.
Additional Diabinese Information
Diabinese - User Reviews
Diabinese User Reviews
Now you can gain knowledge and insight about a drug treatment with Patient Discussions.
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
Find out what women really need.