Answered 10/17/2014 by Samuel Grossman, BS Pharm, Pharm.D, CDE
The majority of the oral medications for diabetes can be taken without regard to meals. There are some exceptions, including the following:
-Metformin can cause stomach aches and nausea and should be taken after meals;
-The class of alpha glycosidase inhibitors (brand name may vary from one country to the other) should be taken with the first bite of the meal.
-The class of sulfonylureas (brand names may vary from one country to the other) should be taken within 30 minutes before eating.
-The class of meglitinides (brand name may vary from one country to the other) should be taken within 15 minutes of a meal 3 times daily.
Evaluating injectable medications:
-GLP-1 agonists, and pramlintide (Symlin) can be injected without regard to meals with the exception of exenatide (Byetta), which is a GLP-1 agonist that is taken twice daily 60 minutes prior to the meal to avoid nausea.
-Premeal insulin such as aspart (Novolog), lispro (Humulog) both should be taken within 15 minutes of the meal and glulisine ( Epidra) can be taken up to 20 minutes after the start of the meal.
-Premeal insulin such as regular insulin can be taken within 30 minutes of the meal.
All other insulin products that do not contain the above premeal insulin and are considered basal or long acting insulin can be taken without regard to meals.