section name header

Quick Reference

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.

Metformin

  • 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® )

Sulphonylureas

  • 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.

DPP-4 inhibitors (gliptins)

  • 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.

Glitazones (insulin sensitisers)

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.