For me xanax helps better than klonopin, but ask her doctor.
Treating older people is a specialty in psychiatry, because they react differently and have to be monitored more closely (not that this actually happens, but there you go). Where are you that it takes a year to see a psychiatrist? Kind of hard to believe. Doctors are not very good at this, but might be able to suggest a geriatric psychiatrist. And you should know, klonopin is considered to be better for regular use than Xanax, which is very short-acting, and they can be very difficult to quit taking if taken regularly, so you do want to see someone with experience. She might need to take two klonopin a day, which is how it's usually prescribed, but an important question is, is there a reason her anxiety has shot up? Does she have a therapist to talk to? Maybe there's an issue here that can be dealt with.
The best advice I can give you is to get your mom to a doctor, if not a psychiatrist. Then her health issues can be evaluated fully, and taken into consideration before any med change is made. Never take or give medication that is not for you or that person, and never for a problem not seen by a doctor for. Doing so can cause alot more harm than good. Blessings - Blu