Glucotrol XL Special Precautions

G6PD Deficiency: Since glipizide GITS belongs to the class of sulfonylurea agents, caution should be used in patients with G6PD deficiency. Treatment of patients with G6PD deficiency with sulfonylurea agents can lead to haemolytic anemia and a nonsulfonylurea alternative should be considered.
Hypoglycemia: All sulfonylurea drugs, including glipizide GITS are capable of producing severe hypoglycemia which may result in coma, and may require hospitalization. Patients experiencing severe hypoglycemia should be managed with appropriate glucose therapy and should be monitored for a minimum of 24-48 hrs.
Proper patient selection, dosage and instructions are important to avoid hypoglycemic episodes. Regular, timely carbohydrate intake, including breakfast, 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 glipizide 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 β-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.
Loss of Control of Blood Glucose: When a patient stabilized on a diabetic regimen is exposed to stress eg, fever, trauma, infection or surgery, a loss of control may occur. At such times, it may be necessary to discontinue glipizide GITS and administer insulin.
The effectiveness of any oral hypoglycemic drug, including glipizide GITS, in lowering blood glucose to a desired level decreases in many patients over a period of time. This 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.
Laboratory Tests: Blood glucose should be monitored periodically. Measurement of glycosylated hemoglobin should be performed and goals assessed by the current standard of care.
There have been no clinical studies establishing conclusive evidence of macrovascular risk reduction with Glucotrol XL or any other antidiabetic drug.
Renal and Hepatic Disease: The pharmacokinetics and/or pharmacodynamics of glipizide GITS may be affected in patients with impaired renal or hepatic function. If hypoglycemia should occur in such patients, it may be prolonged and appropriate management should be instituted.
Gastrointestinal Disease: Markedly reduced GI retention times of Glucotrol XL may influence the pharmacokinetic profile and hence the clinical efficacy of the drug. As with any other nondeformable material, caution should be used when administering Glucotrol XL in patients with preexisting severe gastrointestinal narrowing (pathologic or iatrogenic). There have been rare reports of obstructive symptoms in patients with known structures in association with the ingestion of another drug in this nondeformable sustained-release formulation.
Information for Patients: The risk of hypoglycemia, its symptoms and treatment, and conditions that predispose to its development should be explained to patients and responsible family members. Primary and secondary failure also should be explained. Patients should be informed that Glucotrol XL should be swallowed whole. Patients should not chew, divide or crush the tablets. Patients should not be concerned if they occasionally notice in their stool something that looks like a tablet. In Glucotrol XL, the medication is contained within a non-absorbable shell that has been specially designed to slowly release the drug so the body can absorb it. When this process is completed, the empty tablet is eliminated from the body.
Patients should be informed of the potential risks and advantages of glipizide and of alternative modes of therapy. They should also be informed about the importance of adhering to dietary instructions, of a regular exercise program, and of regular testing of blood glucose.
Effects on the Ability to Drive or Operate Machinery: The effect of glipizide GITS on the ability to drive or operate machinery has not been studied, however, there is no evidence to suggest that glipizide may affect these abilities. Patient should be aware of the symptoms of hypoglycemia and be careful about driving and the use of machinery.
Use in pregnancy: Glipizide GITS was found to be mildly fetotoxic in rat reproductive studies. No teratogenic effects were found in rat or rabbit studies.
Glucotrol XL should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.
Because recent information suggests that abnormal blood glucose levels during pregnancy are associated with a higher incidence of congenital abnormalities, many exports recommend that insulin be used during pregnancy to maintain blood glucose levels as close to normal as possible.
Prolonged severe hypoglycemia (4-10 days) has been reported in neonates born to mother who were receiving a sulfonylurea drug at the time of delivery. If glipizide GITS is used during pregnancy, it should be discontinued at least 1 month before the expected delivery date and other therapies instituted to maintain blood glucose levels as close to normal as possible.
Use in lactation: Although it is not known whether glipizide GITS is excreted in human milk, some sulfonylurea drugs are known to be excreted in human milk. Because the potential for hypoglycemia in nursing infants may exist, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother. If the drug is discontinued and if diet alone is inadequate for controlling blood glucose, insulin therapy should be considered.