SULFONYLUREAS

Tolbutamide; Glibenclamide

Action: • Stimulate pancreas to secrete insulin

Uses: • Only effective in type II [late onset] diabetes

Adverse reactions:

• Hypoglycaemia

• Intolerance to alcohol

Contraindications:

• Juvenile onset diabetes

• Renal & liver impairment

Drug Interactions

• Caution when given with aspirin, phenylbutazone, tetracyclines as these highly protein bound drugs displace sulphonylureas from their body sites exacerbating their hypoglycaemic effect

• Caution when given with beta-adrenergic blockers as they tend to mask the symptoms of hypoglycaemia

BIGUANIDE

Metformin

Action: • Promote peripheral uptake of glucose

Uses: • Only effective in type II [late onset] diabetes

Adverse reactions:

• Hypoglycaemia

• Can cause lactic acidosis

Contraindications:

• Juvenile onset diabetes

• Renal & liver impairment

• > 65 years age

• Caution when given with beta-adrenergic blockers as they tend to mask the symptoms of hypoglycaemia