Methotrexate and possible drug interactions

  To whom it may concern,
  Within the past 2 years my grandfather has been receiving treatment from a HMO health care provider.  During these past two years my grandfather has seemed to develop Cirrhosis of the liver.  My family thinks this is due to improper health supervision.
  My grandfather was prescribed methotrexate for Arthritis purposes in December of 96. His dosage was as follows: 2.5 mg three times weekly.  This was a long term medication in which the doctor never took liver tests to see if the medication was affecting his liver.  Before he started on the methotrexate he was also taking various medications as well, which lead me to believe there was a drug interaction of some sort that lead to my grandfather's illness.  Some of the medications were:  Naproxen 500mg twice daily, Daypro 600mg twice daily, ect.
  I am severely worried about the health of my grandfather.  It seems like something could have been prevented and i was incquiring about this because we are thinking of taking legal action.  My grandfathers health is depleting fast he has lost 60 lbs going from 215lbs to 120lbs within the past year.  He also suffers from severe water build-up, and stomach problems. I was wondering if this may have to due with drug interactions and/or lack of liver testing.
  Thank you so much for the time you take in answering my questions.
  Sincerely,
  Kelly Greenlief
  ***@****
Dear Kelly,
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