Manju,
At lest your GP is thinking out of the box, which makes a change.
I take 3x 1000mg or Omega 3 fish oil supplements every day, up from 1 per day. Have done for years. Oily fish even better.
I'm not actually sure whether these have helped me or not with any pain relief, as I've now took them for such a long time now.
Worth a read:-
http://en.wikipedia.org/wiki/Omega-3_fatty_acid
George.