The first treatments for blood glucose control in people with type 2 diabetes are often meal planning, weight loss, and exercising. Sometimes these measures are not enough to bring blood glucose levels down to the normal range. The next step is taking a medicine that lowers blood glucose levels—usually an oral medication.
But if you are still not achieving optimal results in your diabetes management, you and your doctor might need to make adjustments. There are many different types of oral medications available and each one works slightly differently. You may need to use trial and error to determine which oral medication is best for you.
There is also the possibility of combination therapy, or taking more than one oral medication at the same time. While this has the potential for more negative side effects, research indicates that combination therapy with the oral medication Metformin may be worth the risk and added cost for some people.
Here’s what you should know about all the different types of oral medications available, and when you should consider making adjustments.
Oral medications don’t work for everyone, according to the American Diabetes Association. If you have had diabetes for more than 10 years or already take more than 20 units of insulin per day, they are less likely to be effective. But if you are newly diagnosed with diabetes and have needed little to no insulin, they may help you.
There are many different classifications of oral medications:
Sulfonylureas stimulate the beta cells of the pancreas to release more insulin. Examples include Diabinese (chlorpropamide), Glucotrol and Glucotrol XL (glipizide) Micronase, Glynase and Diabeta (glyburide), and Amaryl (glimepiride). They are generally taken one to two times a day, before meals.
Biguanides lower blood glucose levels primarily by decreasing the amount of glucose produced by the liver. Metformin (Glucophage) is the most common biguanide and helps to lower blood glucose levels by making muscle tissue more sensitive to insulin so glucose can be absorbed.
Meglitinides also stimulate beta cells to release insulin. Prandin (repaglinide) and Starlix (nateglinide) are common examples. It is possible to experience hypoglycemia (low blood glucose levels) when taking meglitinides.
Thiazolidinediones help insulin work better in muscle and fat tissues and also reduce glucose production in the liver. Avandia (rosiglitazone) and Actos (pioglitazone) are common examples. They are effective at reducing A1c and generally have few side effects, though they have been linked to heart problems.
DPP-4 inhibitors are a class of medication that work by preventing the breakdown of a naturally occurring compound in the body, GLP-1, which helps to reduce blood glucose levels. Januvia (sitagliptin), Onglyza (saxagliptin), Tradjenta (linagliptin) and Nesina (alogliptin) are types of DPP-4 inhibitors.
SGLT2 inhibitors cause excess glucose to be eliminated in the urine. Invokana (canagliflozin) and Farxiga (dapagliflozin) were recently approved by the Food and Drug Administration to treat type 2 diabetes. Side effects can include urinary tract and yeast infections.
Alpha-glucosidase inhibitors help to block the breakdown of starches in the intestine. Their action slows the rise in blood glucose levels after a meal, and they should be taken with the first bite of a meal. Precose (acarbose) and Glyset (miglitol) are alpha-glucosidase inhibitors.
Bile acid sequestrants help remove cholesterol from the body, particularly LDL cholesterol, which is often elevated in people with diabetes. Because they are not absorbed into the bloodstream, they are usually safe for use by people with liver problems. Welchol (colesevelam) is the most common example of this type of medication.
New guidelines for oral meds
According to updated guidelines from the American College of Physicians (ACP), Metformin should be the first oral medication prescribed for managing glycemic control in type 2 diabetes, following lifestyle modification.
Metformin is recommended as a first-line treatment because it is cheaper and more effective than other oral medications and is associated with fewer adverse effects; of note, it does not result in weight gain.
But if Metformin alone isn’t working well enough, the ACP guidelines recommend adding additional oral medications.
Certain combination therapies with metformin are more effective than Metformin alone in reducing HbA1c levels, weight, and blood pressure in patients with type 2 diabetes according to the guidelines, published in the Annals of Internal Medicine.
So, the ACP recommends that clinicians consider adding a sulfonylurea, a thiazolidinedione, an SGLT-2 inhibitor, or a DPP-4 inhibitor to Metformin to improve glycemic control when a second oral therapy is considered.
But, they acknowledge, this recommendation is graded as weak because of the fine balance between possible benefits and harms for the various drug combinations. Combination therapies were associated with an increased risk for adverse effects compared to treatment with a single drug.
And there are other factors to consider, such as cost. Adding a second oral medication to Metformin may provide additional benefits; however, the increased cost may not always be worth the added benefit, particularly for the more expensive, newer medications.
You should talk with your doctor and only adjust your oral medications after discussing benefits, adverse effects, and costs.
Have you ever talked with your doctor about adjusting your oral medications? Share your experiences with the community by commenting below.