Downside of metformin

It's sourced from a plant that grows in Europe, so if you want "synthetic" or non-natural meds it's not for you

It tries to prevent your liver from dispensing too much stored sugar and if it works it prevents you from experiencing all the delightful complications of diabetes - so reduces your risk of going blind, having a lower limb amputated, needing dialysis or dying early from heart disease and stroke - so you don't get the "full diabetic experience if the drug works" - is that a negative?

It does cause some G.I. issues (nausea, diarrhea, stomach upset) in almost ALL initial users (or anytime the dose is increased) but typically that subsides in about 2 weeks

If the discomfort continues you could be in the 5-10% of people who just can't tolerate it - there is other drugs, primarily Basil (Long Acting) Insulin that could be substituted (all the other meds you see advertised are for "mealtime sugars" - metformin and Basil Insulin are unique in the blood sugar they treat which comes from the liver)

Gabapentin is a non-opioid pain reliever (nerve blocker)

You can read the laundry list of side effects and they sound like most meds

But the "biggie" in my opinion is -

Gabapentin along with Pregabalin which are used to treat Nerve Pain from Diabetic Peripheral Neuropathy DO NOT TREAT the condition, instead they simply "block" out the nerve pain

So while the Neuropathy is potentially getting worse, which can lead to infections and eventually amputations, the "drug" is taking away all the pain, but the pain only, while things might be getting significantly worse

But at least it won't hurt while that is happening so regular "foot checks" and possibly the consultation of a vascular specialist would be wise if you use a "blocker" for Diabetic Neuropathy (which the drug doesn't treat - only near perfect blood control can halt or slow down Neuropathy once it sets in and the Metformin can help with that blood sugar control)