How do diabetes medicines work
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Have you ever wondered why your physician prescribed a variety of diabetes pills instead of insulin? Do you find yourself pondering over how your medicine is actually helping you manage blood sugar levels? If you do, then we have the answers for you.

Your diabetes regimen may require you to take insulin or diabetes pills, along with maintaining healthy lifestyle habits. Your medication plan is influenced by the type of diabetes you have and your blood sugar levels.1

  • Type 1 diabetes: People with type 1 diabetes need to take insulin since their body does not produce an adequate amount of insulin naturally.
  • Type 2 diabetes: Although insulin is produced in people with type 2 diabetes, their body is unable to use it.2 Some people with type 2 diabetes control blood sugar levels with the help of diet and physical exercise, but others need oral medications. Some may also require insulin.3
  • Gestational diabetes: Some women may be diagnosed with diabetes for the first time when they are pregnant.2 In such cases, regular physical activity and a healthy diet may be sufficient to control blood sugar levels. However, if blood sugar levels cannot be controlled with physical activity and diet, insulin or some diabetes pills may be used. Many diabetes medicines aren’t used while pregnant or when breastfeeding, thus, it is best to ask the doctor what works in your situation.1,4


Glucose is the primary source of energy for the body. The glucose obtained from meals is used up or stored in the body with the help of insulin, which is a natural hormone produced by the pancreas. One can compare insulin to a key for unlocking the doors to our cells so that glucose can enter them. In individuals with type 1 diabetes, the pancreas does not produce insulin. Hence, insulin shots are needed to process the glucose in the body.5,6

Oral medications

Oral diabetes medications are the first line of treatment to manage consistent high blood sugar levels in those with type 2 diabetes. Even if the body produces insulin, oral medicines may be prescribed by your healthcare provider to control blood sugar levels, since the body doesn’t really respond to the produced insulin.5 The different classes of medicines used in diabetes are listed below, along with their mode of action:

  1. Biguanides:

Medicines in this class (e.g., metformin) lower blood sugar levels by helping the glucose to get into the cells more efficiently. They also stop the liver from making too much glucose.2

  1. Dopamine receptor agonists:

These medicines (e.g., bromocriptine) help lower blood sugar levels after a meal.7 They affect the level of the chemical dopamine in the cells.2

  1. Meglitinides:

These medicines (e.g., nateglinide and repaglinide) trigger the pancreas to produce more insulin around mealtimes.2,7

  1. Sulfonylureas:

These medicines, like meglitinides, stimulate the pancreas to produce more insulin (e.g., glimepiride, glyburide, chlorpropamide, glipizide, tolbutamide and tolazamide).2

  1. Alpha-glucosidase inhibitors:

These medications (e.g., miglitol and acarbose) block the breakdown of starches, such as pasta, potatoes and bread, and table sugar in the intestine, thereby slowing down the digestion of sugar.2,7

  1. Bile acid sequestrants:

These medicines (e.g., colesevelam) are not absorbed in the bloodstream; therefore, they are recommended for use in people who cannot take other diabetes pills due to liver problems. Their mode of action is not clear.2,7

  1. Dipeptidyl peptidase-4 (DPP-4) inhibitors:

Our body produces a compound, GLP-1, which reduces the blood sugar in the body. However, as GLP-1 is broken down very quickly, DPP-4 inhibitors are used to prevent its breakdown and allow it to stay longer in the body. These medicines help lower blood sugar levels (e.g., sitagliptin, saxagliptin, alogliptin and linagliptin).7

  1. Sodium-glucose transporter 2 (SGLT2) inhibitors:

Glucose in the blood passes through the kidneys, where it is either excreted with the urine or reabsorbed into the bloodstream. SGLT2 facilitates the re-entry of glucose into the blood in the kidneys. SGLT2 inhibitors (e.g., dapagliflozin, canagliflozin, empagliflozin and ertugliflozin) obstruct the function of SGLT2, thus, preventing the reabsorption of glucose into the bloodstream and also help with the elimination of glucose via urine.2,7

  1. Thiazolidinediones:

These medicines help the cells in your body to utilise glucose better, thereby lowering circulating blood glucose levels (e.g., rosiglitazone, pioglitazone).2

  1. Oral combination therapy

In cases where a single medicine does not effectively manage your blood sugar levels, your doctor may prescribe a combination of one or more of these medicines.7

Your treatment for diabetes may need to change depending on your blood sugar control.8 You should consult your healthcare provider before you alter the dose or stop taking diabetes medicines, as well as before starting any new exercise or diet regimen.8,9

No matter which medicine your doctor prescribes, combine it with a healthy lifestyle to manage your diabetes optimally.9

Remember, using natural methods like diet control and exercise to control your blood sugar is always better than taking a ton of pills!


  1. National Institute of Diabetes and Digestive and Kidney Diseases. Insulin, medicines, & other diabetes treatments [Internet]. [updated 2016 Dec, cited 2019 Nov 13]. Available from:
  2. Food and Drug Administration. Diabetes medicines [Internet]. [cited 2019 Nov 13]. Available from:
  3. American Diabetes Association. Medication management [Internet]. [cited 2019 Nov 13]. Available from:
  4. National Diabetes Education Program. Medicines for diabetes control [Internet]. [cited 2019 Nov 13]. Available from:
  5. American Diabetes Association. Insulin basics [Internet]. [cited 2019 Nov 13]. Available from:
  6. Harvard Medical School. Sugar and the brain [Internet]. [cited 2019 Nov 13]. Available from:
  7. American Diabetes Association. What are my options? [Internet]. [cited 2019 Nov 13]. Available from:
  8. Healthdirect Australia. Diabetes medication [Internet]. [updated 2018 July; cited 2019 Nov 13]. Available from:
  9. Familydoctor. Oral medicines for diabetes [Internet]. [updated 2018 Feb 08; cited 2019 Nov 13]. Available from:

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Disclaimer: The information provided in this article is for patient awareness only. This has been written by qualified experts and scientifically validated by them. Wellthy or it’s partners/subsidiaries shall not be responsible for the content provided by these experts. This article is not a replacement for a doctor’s advice. Please always check with your doctor before trying anything suggested on this article/website.