My 90 Year Old Father Goes To A Doctor At

my 90 year old father goes to a doctor at the v.a.. he also has a doctor he sees through kaiser. Kaiser suggested he quits taking his Digoxin. (maybe because it interacts with his other meds?) The V.A. said he decides but if he stops it and has heart problems he needs to go to the kaiser er and not the V.A. er. because the V.A. suggested he might want to stay on it. Digoxine was prescribed to him a long time ago by a doctor in another state (30 years or more ago) for a heart attack he had in his fourties. My question is: is the digoxine dangerous to take with metoprolol tartrate, levothyroxine,simvastatin,and ffurosemide?