Can Ganaton Be Taken Instead Of Motillium While Having Parkinson's, Alzeimers And Atrial Contraction?

my 83 year old father has parkinsons disease for 6 years now. he also has premature atrial contraction but stable. he also has prostate enlargement & alzeimers disease. He is presently taking madopar 250 mg. 3x a day plus sifrol 250 mcg 2x a day. plus Motillium 10mg 3x a day 30minutes b4 the madopar & sifrol. . . plus of course, other drugs for his other mentioned ailments. . . is it advisable for him to shift to ganaton instead of motillium? he is doing very well with motillium but i heard ganaton is much cheaper. pls advise me.