My 90 Year Old Mother Has Type 2 Diabetes, And

My 90 year old mother has type 2 diabetes, and has recently been told her A1-C has risen to the point she should start taking another medication in addition to Metformin,etc. I assume these medications are prescribed to avoid taking insulin. There are so many negative side effects from Invokana, Januvia, Farxia, Zarelto, etc. Do you think it is necessary for someone at 90 years old to take a chance with so many bad side effects? And how much time will this possibly buy her before she would go on insulin?