Some meds worsen glucose control
Dear Dr. Roach: I have been prediabetic for around 13 years and had been able to keep it that way though diet and exercise — no medications for it. But the real issue now is that I have developed congestive heart failure, which probably sounds worse than it really is. However, the medications I have been given for it (Lasix, spironolactone, carvedilol) from my cardiologist and finasteride for prostate issues have totally ruined my glucose numbers. I used to see around 100 in the mornings. I almost never got to the 120s. Now after a couple months on those drugs I am seeing closer to 150 in the morning. After meals the numbers are running nearly 100 points higher than without them.
So, to fix one issue, I fear the diabetes I have worked so hard to contain is going to become a serious problem. What do I do?
L.H.
Answer: Many medicines can make blood sugar control worse. This can cause a person’s well-controlled diabetes to slip out of control, or take a person with prediabetes and turn them overtly diabetic. Some blood pressure medicines (thiazide-type diuretics, such as HCTZ, some beta blockers), cholesterol medicines (statins, niacin) and psychiatric medicines (many medicines for schizophrenia) are among the most common drugs to do so. It is often difficult to choose medicines to treat one condition while avoiding those that can make a second condition worse. Often, we choose the medications that most help the most life- or healththreatening condition, and deal with the consequences on the other condition as best we can.
In your case, none of the medicines you are on commonly worsen diabetes. Although carvedilol is a beta blocker, it has the least effect (among beta blockers) on blood sugar, and has been reported to have no effect on blood sugars. Finasteride tends to slightly lower blood sugar. Spironolactone and furosemide generally have minimal effects on blood sugar. So, either you are having an unusual reaction to one (or more) of your medicines, or there is something else going on that is making the blood sugar go up.