I have type 2 diabetes treated with Glucophage [metformin], and I also take Niaspan at bedtime to help lower triglycerides. On a normal day, my glucose reading is hardly ever over 130 mg/dl [7.2 mmol/L], but, when I have to fast before a doctor’s appointment, my sugar reading is sky high when I get my blood results back. I am confused and upset about this as my doctor keeps increasing my medication on the pretense that I am not controlling my blood sugar myself. I tried to explain to him what had happened, but he just upped the medication. I also have researched and found that the Niaspan alters blood glucose! Is it possible to have higher readings while fasting than on a regular schedule? What’s a person to do?

You are correct that Niaspan can antagonize blood sugars to a small degree. However, Niaspan has beneficial effects on the qualitative and quantitative abnormalities of lipids in your body that accompany type 2 diabetes.

I would also suggest that if there is this big difference in fasting lab glucose versus fasting fingerstick glucose, I would have a diabetes educator look at your meter to make sure it is giving you accurate information. You should also have a test called a hemoglobin A1c performed every three months. This test gives you your average daily blood sugar over the previous three months. It is more helpful managing the big picture, compared to having a fasting glucose on a single day. If your A1c is not at goal, your physician is correct to make interval changes in your medications to improve your overall level of control.

JTL