Suggest Treatment For Knee Pain While Having Fluid In Knee

HI Doc!!!!! I have an question for my farther,who is in India.he has an very bad knee pain and there was some fluide in his knee and he has removed that fluide just before 2 months and he had changed many doctors but still not much progress..now he has visited one of the doctor in Bombay and he thinks he is well good he has given him this following tablets=RAZO D,FOLVITE,SAZO 500,VOVERAN SR75,DOLO650,METHOTREXATE IP 2.5M.but still he cant see much progress but doctor say he has to continue this medicine only.can u please tell me is all this medicine related to his pain and how far they are sucessfull.

I will be really gratefull if you will answer my question.

Thank you.