Hello dear! I have gone through your query and understood your concerns! Thank you for sharing them on healthcaremagic. Your sore throat to the level you cannot swallow or talk, is not likely due to metformin intake. A bacterial or viral infection is more possible to explain those symptoms. I suggest you to continue the cure of antibiotics your doctor has prescribed you, and then see the improvement. If you don t feel good after the medication, please feel free to ask again to go through a detailed diagnostic process. I hope this answer was helpful to you! I would appreciate a lot if you rate as helpful my answer and write a short review about your experience with me. Thank you and best regards! DR ERIOL