i have been having knee problem for several years. x ray shows thinning of cartilage. I have been prescribed glucosamine as Jointace, Jointace C2 and also Jointace DN. changing the types after three to four months. the dose prescribed was one tablet , 750 mg, a day. My age is 81 years. I have recently ( 1st week May ) had a bypass surgery and also have been given a pace maker. i was advised to stop taking glucosamine. As advised, i am now walking one mile and doing exercise for strengthening knee and thigh muscles, but morning stiffness of the knees appear to be increasing. should I start glucosamine again ? if so , what should be the dose / A . K . Ray