In fact, I have quite a different answer for you.
Do not wait on this situation, take her to be seen now, talk to her doctor right now, or her doctors answering service.
Any suicidal talk requires immediate evaluation, even if it is intermittent.
Just stopping her medicine to night does NOT mean the drug is out of her system, or that she will NOT have suicidal thoughts.
As to her treatment, bi polar individuals will often react to this way to anti depressants. If it is depression, then the answer is not simply to give up on medicine but to use one with a good profile in the elderly, and switch if that does not work.
A psychiatric assessment, and a geriatric assessment are both useful as well, and will help clarify the diagnosis.
I am a double board certified US doctor, find me in medical daily, I will always give you correct, accurate, and safe answers.
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