General

Canada-Approved Medicine

This monograph describes a medication approved for use in Canada by the Therapeutic Products Directorate, a division of Health Canada’s Health Products and Food Branch. The medication is not approved by the United States Food and Drug Administration; however, a similar formulation carrying a different generic or brand name might be available in the US.

Pronunciation:
glik-la-zide

Trade Name(s)

• Diamicron MR 

Ther. Class.

antidiabetics

Pharm. Class.

sulfonylureas

Indications

Control of blood sugar in type 2 diabetes mellitus when control of diet and exercise fails or when insulin is not an option. Requires some pancreatic function.

Action

Lowers blood glucose by stimulating the release of insulin from the pancreas and increasing sensitivity to insulin at receptor sites.

Therapeutic Effect(s):

Lowering of blood glucose in diabetic patients.

Pharmacokinetics

Absorption: Well absorbed following oral administration (97%)

Distribution: Unknown.

Protein Binding: 95%.

Metabolism and Excretion: Extensively metabolized, metabolites are mostly eliminated (60–70%) in urine, 10–20% in feces; <1% excreted unchanged in urine.

Half-life: Tablets: 10.4 hr;  modified-release tablets: 16 hr.

TIME/ACTION PROFILE (effect on blood sugar)

Contraindication/Precautions

Contraindicated in:

• Hypersensitivity; cross-sensitivity with other sulfonylureas may occur;
• Unstable diabetes, type 1 diabetes mellitus, diabetic ketoacidosis, diabetic coma or pre-coma;
• Severe hepatic or renal impairment;
• Concurrent use of oral/oromucosal miconazole, alcohol or alcohol-containing medications, or systemic phenylbutazone;
• OB:  Should not be used during pregnancy; insulin is preferred;
• Lactation: Should not be used during lactation; insulin is preferred.

Use Cautiously in:

• Glucose 6-phosphate dehydrogenase deficiency (↑ risk of hemolytic anemia);
• Infection, stress, or changes in diet may alter requirements for control of blood sugar or require use of insulin;
• Impaired thyroid, pituitary, or adrenal function;
• Malnutrition, high fever, prolonged nausea, or vomiting;
• Pedi:  Safety and effectiveness not established.

Adverse Reactions/Side Effects

Endo: hypoglycemia

GI: ↑ liver enzymes, abdominal pain, diarrhea, dyspepsia, nausea, vomiting

Derm: photosensitivity, rash

* CAPITALS indicate life-threatening.
Underline indicate most frequent.

Interactions

Drug-Drug

• Concurrent use of  alcohol,  angiotensin converting-enzyme inhibitors,  antituberculars,  azole antifungals,  beta-blockers,  clarithromycin,  clofibrate,  disopyramide,  H2–receptor antagonists,  MAO inhibitors,  NSAIDs,  phenylbutazone,  salicylates, long-acting  sulfonamides,  warfarin, may ↑ risk of hypoglycemia.
• ↑ risk of hypoglycemia with other  antidiabetic agents  including  alpha glucosidase inhibitors,  biguanides, and  insulin.
• Concurrent use of  chlorpromazine,  corticosteroids,  danazol,  diuretics  (including  thiazides, and  furosemide),  hormonal contraceptives  (estrogen  and  progestogen ),  nicotinic acid  (pharmacologic doses),  ritodrine,  salbutamol,  terbutaline, or  tetracosactrin  may ↑ risk of hyperglycemia and lead to loss of diabetic control.
• May ↑ risk of bleeding with  warfarin.
• Concurrent use with  alcohol  may result in a disulfiram-like reaction and should be avoided.
•  Beta-blockers  may ↓ some symptoms of hyperglycemia.

Route/Dosage

PO (Adults): Tablets: 80–320 mg/day, doses >160 mg/day should be divided and given twice daily;  modified-release tablets: 30 mg daily, may be ↑ in 30-mg increments every 2 wk until blood sugar is controlled up to 120 mg/day.

Availability

Tablets (contain lactose): 80 mg

Modified-release tablets: 30 mg, 60 mg

Assessment

• Observe for signs and symptoms of hypoglycemia (hunger, weakness, sweating, dizziness, tachycardia, anxiety).
• Assess patient for allergy to sulfonylureas.

Lab Test Considerations:

Monitor serum glucose and glycosylated hemoglobin periodically during therapy to evaluate effectiveness of treatment.

• Monitor liver function periodically in patients with mild to moderate liver dysfunction. May cause ↑ AST, ALT, alkaline phosphatase, and LDH.
• Monitor renal function periodically in patients with mild to moderate renal dysfunction. May cause ↑ creatinine and hyponatremia.

Overdose is manifested by symptoms of hypoglycemia. Mild hypoglycemia may be treated with administration of oral glucose. Treat severe hypoglycemia with IV D50W followed by continuous IV infusion of more dilute dextrose solution at a rate sufficient to keep serum glucose at approximately 100 mg/dL.

Implementation

• Patients on a diabetic regimen exposed to stress, fever, infection, trauma, or surgery may require administration of insulin.
• PO Administer with meals at the same time every day.

Patient/Family Teaching

• Instruct patient to take gliclazides as directed at the same time every day.
• Explain to patient that this medication does not cure diabetes and must be used in conjunction with a prescribed diet, exercise regimen, to prevent hypoglycemic and hyperglycemic events.
• Instruct patient on proper technique for home glucose monitoring. Monitor closely during periods of stress or illness and notify health care professional if significant changes occur.
• Review signs of hypoglycemia and hyperglycemia with patient. If hypoglycemia occurs, advise patient to drink a glass of orange juice or ingest 2–3 tsp of sugar, honey, or corn syrup dissolved in water or an appropriate number of glucose tablets and notify health care professional.
• Encourage patient to follow prescribed diet, medication, and exercise regimen to prevent hypoglycemic or hyperglycemic episodes.
• Concurrent use of alcohol may cause a disulfiram-like reaction (abdominal cramps, nausea, flushing, headaches, and hypoglycemia).
• Instruct patient to avoid sun exposure and to wear protective clothing and sunscreen when outdoors.
• Caution patient to avoid other medications, especially aspirin and alcohol, while on this therapy without consulting health care professional.
• Advise patient to notify health care professional promptly if unusual weight gain, swelling of ankles, drowsiness, shortness of breath, muscle cramps, weakness, sore throat, rash, or unusual bleeding or bruising occurs.
• Advise patient to inform health care professional of medication regimen prior to treatment or surgery.
• Advise patient to carry sugar packets or candy, and identification describing diabetes diagnosis and medication regimen.
• Rep:  Insulin is the recommended method of controlling blood sugar during pregnancy. Counsel female patients to use a form of contraception other than oral contraceptives and to notify health care professional promptly if pregnancy is planned or suspected.
• Emphasize the importance of routine follow-up exams.

Evaluation/Desired Outcomes

Control of blood glucose levels to avoid episodes of hypoglycemia and hyperglycemia.