Gliclazide Oral: Dosing and Precautions

Therapeutic action

Sulfonylurea antidiabetic.

Indications

• Second-line treatment of type 2 diabetes in patients over 60 years as monotherapy when metformin is not tolerated or contraindicated.
• In combination with metformin when glycaemic control is inadequate with metformin alone.

Forms and strengths

• 80 mg scored tablet.

Dose and duration

Adult:

• Weeks 1 and 2: 40 mg once daily in the morning.
• Increase if necessary in increments of 40 mg every 2 weeks according to blood glucose levels. Weeks 3 and 4: 80 mg once daily in the morning.
• The usual dose is 80 to 160 mg daily, maximum 240 mg daily.

Contra-indications, adverse effects, precautions

• Do not administer in the event of allergy to sulfonamides, type 1 diabetes, juvenile diabetes, ketoacidosis, or severe renal or hepatic impairment.
• May cause hypoglycaemia, gastrointestinal disturbances, weight gain, and rarely allergic reactions.
• Monitor combination with diuretics, ACE inhibitors, NSAIDs, azole antifungals, ciprofloxacin, erythromycin, and co-trimoxazole because hypoglycaemic effect may be enhanced.
• Rifampicin decreases hypoglycaemic effect.
• Corticosteroids, hydrochlorothiazide, salbutamol, and chlorpromazine may increase blood glucose.
• Avoid combination with alcohol because of the risk of hypoglycaemia.
• Pregnancy: avoid. Insulin is the drug of choice for type 2 diabetes in pregnant women.
• Breast-feeding: contraindicated.