Hi, welcome to our site. I am Dr Saumya Mittal. Read your query. That is a very significant question and i appreciate your problem. I will try my best to answer your query Januvia is a different medicine altogether. It cannot be said as to what medicine it is being used as a replacement especially, since you have not mentioned your sugar status/ However metformin usually causes pain in abdomen and so i am assuming it is to replace that have your sugars rechecked within 7 days. please do call with details for further opinion I hope this helps you. Inform the reports mentioned above so i can be of help further. Best of luck. I have given you the answer to the maximum considering the information provided. The results of the tests could further enhance my answer to you. Please do understand that some details could be extracted from a detailed history and examination. Looking forward to your return query with the details asked so that I can help you further. (If the answer has helped you, please indicate this)