Options for metformin?

I'm American and my health provider won't prescribe metformin for prediabetes (had fasting glucose of 115). She said they won't prescribe it for that (I suggested she do some research), but that they would for low blood sugar :|

She said they could refer me to a specialist for that. Which takes months.

I've been on metformin for many years but running low (in Thailand it's OTC and brought some with me to the States).

Any suggestions how to go about this? Very frustrating having these basic meds being prescription only. Incredibly, insulin is OTC :|