When you review medication options with your physician, there are 6 things you should consider, in order of importance.
Your pattern of hyperglycemia
This is one of the most important aspects in choosing an appropriate medication to treat your diabetes. Some people with diabetes have their highest sugars upon awakening in the morning. This frequently occurs independently of food intake, and is due to unrestrained liver glucose output during the night. This pattern of sugar elevation is known as “fasting hyperglycemia”. In other people, sugar levels are highest after a meal. This is known as “post-prandial hyperglycemia”. People with fasting hyperglycemia are most effectively treated with Metformin or a basal insulin such as Lantus or Levemir. Other medications which effectively lower fasting hypgerglycemia include the sulfonylureas (drugs such as Glimperide and Glipizide), Victoza (a long-acting GLP-1 agonist), and Actos. Byetta (a short-acting GLP-1 agonist) and the DPP-4 inhibitors (Januvia, Onglyza, and Tradjenta) will also lower fasting glucoses, although less effectively than the previously mentioned medications. In people with sugars which are highest after meals, treatment options include the DPP-4 inhibitors, the meglitinides (Prandin, Starlix), Precose and the rapid acting bolus insulins (Novolog, Apidra, and Humalog). Precose use has been limited due to frequent complaints of gas. Other options to lower after-meal sugars include the sulfonylureas, Byetta, and Actos. Finger-stick blood sugar testing, both before and after meals, will help you determine when your sugar levels are most elevated.
Your degree of hyperglycemia
The American Diabetes Association (ADA) recommends an HA1c goal of 7%, fasting glucoses of 140 mg/dl, and 2-hour after meal glucoses of 180 mg/dl. The American Association of Clinical Endocrinologists (AACE) recommends an HA1c goal of 6.5%, fasting glucoses of 110 mg/dl, and 2-hour after meal glucose of 140 mg/dl. Oral diabetes medications typically lower HA1c levels by 2% or less. Fasting and after-meal blood sugar levels are typically reduced by 40 mg/dl or less. If your HA1c levels are 2% above goal (i.e 9%), or your blood sugar levels are 40 mg/dl above goal, insulin is your best treatment option. The effectiveness of insulin is “open-ended”. There is not a maximum dose. As you increase your insulin dose, sugar levels will continue to decrease. This is not true with oral diabetes agents and the GLP-1 analogues. All have maximum effective doses. Once the maximum doses are reached, further dose increases will not result in additional benefits. If your HA1c and blood sugar levels are close to the ADA or AACE goals, oral diabetes medications are appropriate options. The oral agents with the greatest glucose reducing capabilities are Metformin, the sulfonylureas, the meglitinides and Actos. Victoza and Byetta are somewhat less effective in lowering sugar levels. The DPP-4 inhibitors are the least effective glucose lowering agents with an average HA1c reduction of 0.8%.
Concern re hypoglycemia
Hypoglycemia may be a significant, potentially life-threatening risk in people with diabetes and active heart disease, as well as in those without typical warning symptoms of hypoglycemia (hypoglycemic unawareness). In this setting, diabetes medications with a low risk for hypoglycemia should be considered. Medications which are not associated with hypoglycemia (when used alone) include Metformin, Victoza, Byetta, the DPP-4 inhibitors, Precose and Actos. Given their association with hypoglycemia, the sulfonylureas should be avoided in patients in whom hypoglycemia represents an unacceptable risk. Long-acting sulfonylureas such as Glyburide carry the greatest risk for significant hypoglycemia. Meglitinides are also associated with an increased risk of hypoglycemia.
Your lifestyle
If you frequently skip meals, or eat at unpredictable times, drugs which are associated with hypoglycemia, such as the sulfonylureas, should be avoided. If a meal is missed or delayed when using a sulfonylurea, you will be at risk for hypoglycemia. Drugs which don’t cause hypoglycemia, such as Metformin, the DPP-4 inhibitors, Precose, Victoza, Byetta and Actos, are an option in this setting.
Consideration may also be given to the meglitinides.
Although the meglitinides work by increasing insulin secretion, and may cause hypoglycemia, they are short acting, and are taken only when you eat a meal. If you have a difficult time remembering to take medications, or already take many different medications, long-acting once-daily medications may be preferred to drugs which require 2-3x daily dosing. Once daily medications include the long acting sulfonylureas (Glipizide ER), Metformin XR, the DPP-4 inhbitors, Victoza and Actos. The basal insulins Lantus and Levemir may also be effective with once daily dosing. It should be noted that the long acting sulfonylureas and metformin are occasionally dosed twice daily. Combination diabetes medications, such as Janumet (Januvia and Metformin), may also be an option to simplify your regimen. These medications combine two different medications in one pill.
Your weight
Obesity is a common problem in people with diabetes. The only diabetes medications associated with consistent weight loss are the GLP-1 agonists, Byetta and Victoza. After 6 months of therapy with any of these medications, the typical weight loss is 6 pounds. Metformin, the DPP-4 inhibitors, and Precose are weight neutral. This means they neither cause weight gain nor weight loss. A recent study reported a 19 pounds weight loss after 2 years of treatment with Byetta and Metformin. The sulfonylureas, Insulin, and Actos are associated with weight gain. Insulin and the sulfonylureas are associated with weight gain which is typically less than 5 pounds. Actos may be associated with a weight gain of as much as 20-30 pounds.
Costs
If your medications aren’t covered by insurance, cost may be a significant concern. The best options in this setting are Metformin and the sulfonylureas. These drugs are available in inexpensive generic formulations. There are other factors, such as interaction with medications and underlying diseases, such as kidney disease, which will also impact your medication choices and should be discussed with your physician.
Understand your treatment options.
Work with your physician to select the medication which “fits you” the best. Become involved in the care of your diabetes, and make a positive impact on your life, starting today.