I guess it’s time to chime in here.
First-I offer metformin to prediabetics with HBA1C >6% but I offer a choice since the data is not absolutely clear. While metformin does seem to decrease the rate of progression to full-blown diabetes, the effect is less than that of diet and exercise and there is no good data combining both. You also run into the problem of having to explain that while a HBA1C of 6.5 is considered good control on diet and exercise, you are recommending starting “diabetes medication” for a level that is already considered better than ideal. Metformin is also not without side effects (nausea, diarrhea and let us not forget that it is a big-ass pill that should not be crushed and a LOT of my patients literally cannot swallow it-and I do mean LITERALLY). That said-I do strongly encourage metformin for all prediabetics and certainly as a first line therapy for diabetics.
There is also the issue of patients being extremely resistant to injectables. In addition, there is a price issue. When you are dealing with Medicare patients who have to pay for multiple medications, you have to remember that the only inexpensive generics are metformin and sulfonylureas. Insulin is not cheap (I paid $500 for about a 4 month supply for my cat-and she only takes 6-8 units a day while my patients often take more than 20 times as much). Needles for insulin pens cost me $45 for 100 needles. The companies that make the GLP-1s, the SGLT-2s and the DPP4s all provide coupons that bring the monthly cost down to anywhere from$0-25 monthly but they cannot be used for any patient with government insurance, which includes Medicare, which leaves patients paying up to $400 monthly for their pills-especially when they get into the “doughnut hole” with Medicare. Sulfunylureas cost literally pennies.
The 2016 AACE/ACE algorithm goes as follows:
Metformin
GLP-1
SGLT-2
DPP4
TZD
Basal insulin
Others
However, given the side effects of SGLT-2s and the resistance to injectables (as well as patient concerns when they read about medullary thyroid cancer), I often end up skipping to the DPP4s, which tend to be well-tolerated and are easy to take since they come in combination with metformin.
Also remember that when you have a patient with significant renal insufficiency or heart failure, you are even more constrained in your choice of medications.
In short, sulfonylureas are low on my list but there are circumstances where they are still a viable option.