While safe for most people, metformin is a prescription drug that needs oversight by a physician due to potentially serious side effects.  A simple evaluation will determine if you are a candidate to take metformin.
 
The evaluation consists of a blood test for 10 different metabolic markers and a questionnaire:
 
Blood sugar
Kidney Function
Liver Function
Sodium
Potassium
Calcium
Chloride
Carbon dioxide
Vitamin B12
Vitamin B9 (Folic Acid)
 
You will receive an email when the order is created.  You can then go to a Quest Diagnostics Center near you to do the blood test.