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Some common oral medications for diabetes are alpha-glucosidase inhibitors and biguanides.

Most Common Oral Diabetes Medications

Did you know that among those diagnosed with diabetes, women are more likely than men to not take their medications? 14.9% of women do not take their oral diabetes medications as prescribed, compared to men, at 11.6%. In addition, adults under the age of 65 are much more likely than those over the age of 65 to not take their medications (17.9% and 7.2% respectively).

Though there are many factors at play, one of the driving factors is likely related to cost. According to GoodRX, the average cost of diabetes medications increased by 58% since 2014. Unfortunately, the cost of insulin has driven these statistics up, as this has increased by 54%, and the cost for diabetes patients are about twice as high as those for the average patient.

Fortunately, there are various options available to patients. Here we take a look at a variety of oral diabetes medications, so you can know your options and find what is right for you.

Alpha-Glucosidase Inhibitors

You may know them as acarbose (Precose) and miglitol (Glyset).

How they work: Alpha-glucosidase inhibitors work by blocking the breakdown of carbohydrates in the intestines. Examples of carbohydrates include pasta, rice, breads and fruit. By blocking the breakdown of these types of foods, blood sugar levels will rise much slower after meals. In order to work effectively, these medications should be taken with the first bite of the meal.

Side effects: The most common side effects include gas and diarrhea.


These may be known as metformin (Glucophage).

How they work: Metformin is the first-line medication used to treat type 2 diabetes – probably because it works in several different ways! First of all, it is an insulin sensitizer. This means that that it allows the body to use insulin more effectively, reducing insulin resistance. It allows the body to absorb less sugar, meaning that if you consume an ice cream cone, you will absorb less of the sugar in the ice cream. Your body also produces glucose from your liver. When you take metformin, you will reduce that sugar production.

Side effects: Metformin can cause some gastrointestinal issues – most commonly diarrhea and nausea. Fortunately, these side effects tend to reduce over time. If these side effects do not improve, most people do well on the extended-release version. In addition, you can reduce the side effects by taking the medication with food or increasing your dosage slowly.


You may know them as:

  • Chlorpropamide (Diabinese)
  • Glimepiride (Amaryl)
  • Glipizide (Glucotrol and Glucotrol XL)
  • Glyburide (Micronase, Glynase and Diabeta)

How they work: Sulfonylureas work by stimulating the beta cells of the pancreas, which are the producers of insulin, to secrete more insulin into the body. They are typically taken one to two times per day.

Side effects: Because they are working directly on insulin production, they can cause hypoglycemia.


These medications are commonly known as nateglinide (Starlix) and repaglinide (Prandin)

How they work: These work similarly to sulfonylureas.They also stimulate the pancreas to make more insulin. They are short-acting and are taken before each meal.

Side effects: They may cause hypoglycemia, especially if taken with a meal that does not contain carbohydrates, or if it is taken at incorrect times.

Thiazolidinediones (TZDs)

You may know them as rosiglitazone (Avandia) and pioglitazone (Actos).

How they work: TZDs are insulin sensitizers and they allow the body to use insulin more effectively. They also reduce the liver’s excretion of glucose.

Side effects: These medications should not be used in people with chronic kidney disease or heart failure, as they can cause weight gain and heart issues if these issues are already present. They can also cause fractures. Avandia may also increase the risk of bladder cancer.

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DPP-4 inhibitors

You may know them as:

  • Saxagliptin (Onglyza)
  • Sitagliptin (Januvia)
  • Linagliptin (Tradjenta)
  • Alogliptin (Nesina)

How they work: DPP-4 inhibitors work with the incretin system – a complex system of hormones that work with the digestive system. They ultimately assist with the excretion of insulin when the glucose is rising due to food intake.

Side effects: Side effects are rare, but upper respiratory infections, sore throat and headaches have been reported.

SGLT-2 Inhibitors

These medications are often known as:

  • Dapagliflozin (Farxiga)
  • Canagliflozin (Invokana)
  • Empagliflozin (Jardiance)
  • Ertugliflozin (Steglatro)

How they work: SGLT-2 inhibitors work by preventing the kidneys from retaking glucose. Instead, excess glucose is released through the urine.

Side effects: These medications can cause urinary tract infections and yeast infections. In rare cases, they can even cause serious genital infections. All of these can be significantly reduced by staying hydrated because excess glucose will pass much easier.

GLP-1 Agonists

These are commonly known as:

  • Albiglutide (Tanzeum)
  • Dulaglutide (Trulicity)
  • Exenatide (Byetta. Bydureon)
  • Liraglutide (Saxenda, Victoza)
  • Lixisenatide (Adlyxin)
  • Semaglutide (Ozempic, Rybelsus)

How they work: Similar to DPP-4 inhibitors, GLP-1 agonists work on the incretin system. GLP-1 agonists are a much stronger medication. Most of these medications are given by injection, with the exception of Rybelsus. All medications can cause weight loss and suppress hunger.

Side effects: Because of how strong these medications are, they can cause nausea and vomiting. They may also cause pancreatitis and in very rare instances, they may increase the risk of certain thyroid tumors.