If it is endstage liver disease and he is not a candidate for a liver transplant, there is no conventional medical treatment that stops the progress.
However, that does not mean nothing can be done. He should be in hospice, which means there is a doctor and nursing to keep him comfortable through the process.
At 90 he will not qualify for a liver transplant, as he would not survive the surgery.
On the other hand, this can be managed effectively and he needs a hospice doctor as well as a liver doctor involved in his care, if not already done.
Sorry about your dad.
OK, so that is an initial answer….
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