Gliclazide is used to lower blood sugar levels in patients with diabetes mellitus type 2 (non-insulin dependent) along with a proper diet and exercising. 

Do not take Gliclazide:

• If you’re allergic to Gliclazide, sulfonylurea, sulfonamides or any other component of this medicine. 
• If you have diabetic ketoacidosis (an emergency condition where your blood sugar levels are very high and you experience nausea, frequent urination, fatigue and muscle weakness).
• If you are in a diabetic coma.
• If you have severe liver problems.
• If you have kidney problems.
• If you are recovering from an injury, operation, infections with fever, or from other forms of stress.
• If you have porphyria (a hereditary disease affecting the liver or bone marrow).
• If you are taking the antifungal Miconazole.