Antidiabetic Drugs: Oral Drugs and Incretin Mimetics - Quick Reference
This is a Quick Reference article. See also the main article Oral antidiabetic drugs and GLP-1 analogues in the treatment of type 2 diabetes Oral Antidiabetic Drugs and GLP-1 Analogues.
- The drug of choice
- Initially 500 mg in the morning, increased by 500 mg at weekly intervals. The slow dose increase may improve tolerance. Max. dose 3 g daily, divided into 2-3 doses.
- Does not cause hypoglycaemia.
- Contraindicated in significant renal impairment (GFR under 60 ml/min)
- Available as a combination product with pioglitazone (Competact® ), sitagliptin (Janumet® , Velmetia® ) and vildagliptin (Eucreas® )
- Agents
- Glibenclamide 3.5-14 mg daily; doses over 7 mg daily must be divided into two doses
- Glimepiride 1-6 mg daily; usually administered once daily
- Glipizide 2.5-30 mg daily; doses over 15 mg daily must be divided into two doses
- May cause hypoglycaemia as they augment insulin secretion regardless of blood glucose concentration.
- Initially the dose may be small, but it should be rapidly increased.
- Not recommended as monotherapy for first-line treatment unless particularly indicated
- If treatment has continued long and is problem free, there is no need to change medication.
- Can be combined with metformin and insulin.
Meglitinides (glinides)
- Agents
- Nateglinide (Starlix® ) 60-180 mg/meal, max. 540 mg daily
- Repaglinide (Novonorm® and generic preparations) 0.5-4 mg/meal, max. 16 mg daily
- Administered with meals
- Rapid onset of action in less than 30 minutes with variable duration of activity, typically less than 3 hours
- Action is dose dependent requiring estimation of dietary carbohydrate content.
- As with mealtime insulin, dose should be varied according to amount of dietary carbohydrate.
- Particularly suitable for patients with high postprandial blood glucose but only slightly elevated fasting blood glucose
- Despite the short duration of activity may cause significant hypoglycaemia.
- Can be combined with metformin.
- Agents
- Sitagliptin (Januvia® ) 100 mg once daily
- Vildagliptin (Galvus® ) 100 mg daily divided into two doses (when combined with a sulphonylurea, 50 mg daily in the morning)
- Saxagliptin (Onglyza® ) 5 mg once daily
- Linagliptin (Trajenta® ) 5 mg once daily
- Stimulate glucose-dependent insulin secretion and can therefore be used to manage postprandial hyperglycaemia.
- Can be combined with all other oral antidiabetic drugs.
- Sitagliptin and vildagliptin are also marketed as combination products with metformin (for trade names, see above).
Incretin mimetics (GLP-1 receptor agonists)
- Agents
- Exenatide by injection (Byetta® ) initially 5 micrograms twice daily, increased if necessary after 1 month to 10 micrograms twice daily
- Liraglutide by injection (Victoza® ) initially 0.6 mg once daily, increased if necessary after at least 1 week to 1.2 mg once daily
- Exenatide for once-weekly injection (Bydureon® ; produced by utilizing microparticle technology): 2 mg once weekly s.c.
- Stimulate glucose-dependent insulin secretion and can therefore be used to manage postprandial hyperglycaemia.
- Promote significant weight loss.
- The most common adverse effect is nausea particularly at start of treatment, which can be considerably reduced by increasing the dose slowly to the maintenance dose.
Glucose reuptake inhibitors (dapagliflozin)
- Agents
- Dapagliflozin (Forxiga® ): normal initiation and maintenance dose 10 mg/day, in liver failure 5 mg/day
- The drug is not recommended in moderate renal failure nor in severe liver failure.
- Can be combined with other antidiabetic drugs, also with insulin in type 2 diabetics.
- Increases the occurrence of urinary tract and genital infections (e.g. vulvovaginitis, balanitis). The drug must be discontinued if the patient develops pyelonephritis or urosepsis.