Summary of oral drug treatments for type 2 diabetes

DrugMean HbA1c reduction Risk of hypo-glycaemiaEffect on weight AdvantagesDisadvantages
Metformin1.5 — 2%Low Neutral
(or small weight loss)
· Patient-orientated outcome data for improvement in micro– and macro-vascular disease

· GI disturbance
· Vitamin B12 deficiency and lactic acidosis (rare)
· Reduce dose in renal impairment
· Remember ‘sick day rules’

Sulfonylureas

Glibenclamide
Gliclazide
limepiride
Glipizide
Tolbutamide
1.5 — 2%Yes 1 to 5kg increase · Rapid response achieved
· Patient-orientated outcome data for improvement in microvascular disease
· Risk of hypoglycaemia
· Caution in renal and liver impairment
· Caution in the elderly
· Driving implications
· Undetermined cardiovascular risk
Pioglitazone1 — 1.5%Low Increase · Can be used in renal impairment · Contraindicated in heart failure
· Contraindicated in hepatic impairment
· Contraindicated in bladder cancer or uninvestigated macroscopic haematuria
· Risk of bone fracture
· Caution in macular oedema
DPP-4 inhibitors

Alogliptin
Linagliptin
Saxagliptin
Sitagliptin
Vildagliptin
0.6 — 0.8%LowNeutral · Generally well tolerated
· Can be used in renal impairment
· Established cardiovascular safety
· Association with pancreatitis (very rare)
· Heart failure reported in people taking alogliptin and saxagliptin
SGLT-2 inhibitors

 Canagliflozin▼
 Dapagliflozin▼
 Empagliflozin▼
1%Low Decrease · Cardioprotective data for empagliflozin
· Weight loss
· Decrease in blood pressure

· GU infections
· Sufficient renal function needed to maintain efficacy
· Remember ‘sick day rules’
· Hypotension / fainting: caution in frail elderly or people taking loop diuretics
· Rare association with euglycaemic diabetic ketoacidosis