Oral Medications for Diabetes
There are two major types of diabetes, type 1 which was once called juvenile diabetes, and type 2 diabetes – previously referred to as adult-onset diabetes. Type 1 affects about 1 in 100 Americans “Diabetes Medications: The next Generation of Oral Agents, Insulin and more” by Donna Ellis in MedSurg Nursing, July/August 2013, volume 22, issue #4); it is usually diagnosed in children, thus its original name. It starts with the body’s immune system attacking and destroying the cells in the pancreas that make insulin. Because insulin is needed to allow glucose to move into muscle and fat cells, without it those cells burn fat for energy and the pH level of the blood drops dramatically. This is an emergency. Those with this type of diabetes require insulin replacement and the oral diabetes medication would not help them.
Type 2 diabetes is much more common, affecting about 10% of Americans (Ellis, 2013). It develops much more slowly and there is often a long period before diagnosis when the pancreas makes too much insulin. This occurs because the insulin receptors, molecules on fat and muscle cells that the insulin fits into to have its effect, are not working properly. This abnormality in the receptors is called insulin resistance. The extra insulin helps get the glucose into cells and prevents the buildup of glucose in the bloodstream where too much glucose can damage arteries and other tissues. The high levels of insulin make it difficult to lose weight since insulin enhances fat storage.
When the pancreas can no longer keep up with the excess insulin production, the blood glucose (also called blood sugar) level rises. It is at this point that diabetes can be diagnosed. Treatment may include diet changes, weight loss, and exercise. Medications can be started to help lower the blood sugar level.
One group of medications used is the sulfonylureas. These medications increase production of insulin by the pancreas. They have been used for years but the newer, second generation sulfonylureas are most often used. Because they increase insulin secretion, they can cause hypoglycemia, an abnormally low blood sugar. This is a dangerous situation because the brain relies on the glucose in the blood. Not surprising, many of the symptoms of hypoglycemia are caused by the lack of glucose in in the brain such as headache, irritability, shakiness, and even confusion if it gets severe, confusion. It has to be treated quickly with something high in sugar such as orange juice or regular soda. Per an article in Diabetic Medicine (C. L. Edridge et al, March 2015) about hypoglycemia caused by diabetes medications, in a one month period more than 50% of those with type 2 diabetes had an episode of hypoglycemia in the month before the study was conducted.
Sulfonylureas can also contribute to weight gain. Because of these side effects and the way these drugs can advance pancreatic beta cell burnout, some recommend the use of sulfonylureas (“A dynamic duo for T2DM” by C. Winter, in Nurse Practitioner Perspective, July/August 2015).
Biguinides in another class of oral medications for diabetes. This has become first-line treatment. It lowers the blood glucose level by decreasing the breakdown of the storage form of glucose in the liver. Because it doesn’t increase insulin production, it doesn’t cause hypoglycemia. It can cause diarrhea, especially when treatment is started at a high dose.
Glitazones are medications that make the insulin receptors more sensitive to insulin. They can cause the body to retain fluids and this can potentially worsen heart failure.
Alpha glucosidase inhibitors decrease the breakdown of complex carbohydrates like bread into simple sugars like glucose. These drugs are particularly helpful in decreasing the after meal rise in blood sugar. Side effects they can cause include flatus and diarrhea. They don’t lower the average blood sugar as much as the other oral diabetes medications. This is measured by a test called a hemoglobin A1C. It measures how much glucose is attached to red blood cells and the level goes up the more glucose the cells are exposed to so it is much better at gauging diabetes management.
Adherence is a common issue for the treatment of many chronic illness. In “Failure to Reach Target Glycosylated A1C Levels Among Patients with Diabetes Who Are Adherent to Their Antidiabetic Medication” by D. Juarez, et al (Population Health Management, Volume 17, number 4, for 2014) the compliance rate for diabetes medication use ranges from 67 to 85%. This article studied the records of thousands of patients that were deemed adherent to their medication regime. Adherence was assessed based on patients getting their medications refilled. 56.1% of such compliant patients were deemed to have poor control of their diabetes. This was quantified as having a hemoglobin A1C of >7%. One of the responses to this low rate of success was that diet, weight management and/or exercise were not being fully attended to. There are certainly other possibilities, some of which they suggested. But, as was noted in C. Winter’s article, diet and exercise can lower the glycosylated hemoglobin (hgb A1C) by 1 to 2%. This is a significant decrease and perhaps an area that needs to be emphasized.
This article is not intended to replace your health care provider. The intent is to make important information about medications available.