Healthy lifestyle choices — including diet, exercise and weight control — provide the foundation for managing type 2 diabetes. However, you may need medications to achieve target blood sugar (glucose) levels. Sometimes a single medication is effective. In other cases, a combination of medications works better.

The list of medications for type 2 diabetes is long and potentially confusing. Learning about these drugs — how they're taken, what they do and what side effects they may cause — will help you discuss treatment options with your doctor.

Several classes of type 2 diabetes medicines exist. Each works in different ways to lower blood sugar. A drug may work by:

  • Stimulating the pancreas to produce and release more insulin
  • Inhibiting the production and release of glucose from the liver
  • Blocking the action of stomach enzymes that break down carbohydrates
  • Improving the sensitivity of cells to insulin
  • Inhibiting the reabsorption of glucose in the kidneys
  • Slowing how quickly food moves through the stomach

Each class of medicine has one or more drugs. Some of these drugs are taken orally, while others must be injected.

Here's an at-a-glance comparison of common diabetes medications. More medications are available depending on your needs and situation. Ask your doctor about your options and the pros and cons of each.

Oral medications

Meglitinides

  • Medications
    • Repaglinide (Prandin)
    • Nateglinide (Starlix)
  • Action
    • Stimulate the release of insulin
  • Advantages
    • Work quickly
  • Possible side effects
    • Low blood sugar (hypoglycemia)
    • Weight gain
    • Nausea or vomiting
    • Headache

Sulfonylureas

  • Medications
    • Glipizide (Glucotrol)
    • Glimepiride (Amaryl)
    • Glyburide (DiaBeta, Glynase)
  • Action
    • Stimulate the release of insulin
  • Advantages
    • Work quickly
  • Possible side effects
    • Hypoglycemia
    • Weight gain
    • Skin rash

Dipeptidyl-peptidase 4 (DPP-4) inhibitors

  • Medications
    • Saxagliptin (Onglyza)
    • Sitagliptin (Januvia)
    • Linagliptin (Tradjenta)
  • Action
    • Stimulate the release of insulin
    • Inhibit the release of glucose from the liver
  • Advantages
    • Don't cause weight gain
  • Possible side effects
    • Upper respiratory tract infection
    • Sore throat
    • Headache

Biguanides

  • Medications
    • Metformin (Fortamet, Glucophage, others)
  • Action
    • Inhibit the release of glucose from the liver
    • Improve sensitivity to insulin
  • Advantages
    • May promote modest weight loss and modest decline in low-density lipoprotein (LDL), or “bad,” cholesterol
  • Possible side effects
    • Nausea
    • Diarrhea
    • Very rarely, the harmful buildup of lactic acid (lactic acidosis) when used in patients with kidney failure

Thiazolidinediones

  • Medications
    • Rosiglitazone (Avandia)
    • Pioglitazone (Actos)
  • Action
    • Improve sensitivity to insulin
    • Inhibit the release of glucose from the liver
  • Advantages
    • May slightly increase high-density lipoprotein (HDL), or "good," cholesterol
  • Possible side effects
    • Heart failure
    • Heart attack
    • Fractures
    • Increased risk of bladder cancer with pioglitazone

These medications shouldn't be used in people with kidney disease or heart problems.

Alpha-glucosidase inhibitors

  • Medications
    • Acarbose (Precose)
    • Miglitol (Glyset)
  • Action
    • Slow the breakdown of starches and some sugars
  • Advantages
    • Don't cause weight gain
  • Possible side effects
    • Stomach pain
    • Gas
    • Diarrhea

Sodium-glucose transporter 2 (SGLT2) inhibitors

  • Medications
    • Canagliflozin (Invokana)
    • Dapagliflozin (Farxiga)
    • Empagliflozin (Jardiance)
  • Action
    • Block glucose from being reabsorbed by the kidneys
  • Advantages
    • May promote weight loss and lower blood pressure
  • Possible side effects
    • Urinary tract infections; yeast infections

Bile acid sequestrants

  • Medications
    • Colesevelam (Welchol)
  • Action
    • Lower cholesterol and have a very modest effect in lowering blood glucose when used in combination with other diabetes medications
  • Advantages
    • Likely safe for people with liver problems
  • Possible side effects
    • Flatulence
    • Nausea
    • Constipation

Injectable medications

Amylin mimetics

  • Medications
    • Pramlintide (Symlin)
  • Action
    • Stimulate the release of insulin
    • Used with insulin injections
  • Advantages
    • May suppress hunger
    • May promote modest weight loss
  • Possible side effects
    • Hypoglycemia
    • Nausea or vomiting
    • Headache
    • Stomach pain

Incretin mimetics

  • Medications
    • Exenatide (Byetta)
    • Exenatide extended release (Bydureon)
    • Liraglutide (Victoza)
  • Action
    • Stimulate the release of insulin
    • Used with metformin and sulfonylurea
  • Advantages
    • May suppress hunger
    • May promote modest weight loss
    • One injection weekly for extended release
  • Possible side effects
    • Nausea or vomiting
    • Headache
    • Dizziness
    • Increased risk of inflamed pancreas (pancreatitis) and some thyroid tumors

No single diabetes treatment is best for everyone, and what works for one person may not work for another. Your doctor can determine how a specific medication or how multiple medications may fit into your overall diabetes treatment plan and help you understand the advantages and disadvantages of specific diabetes drugs.

Sep. 20, 2014