My left knee makes cracking sound if I fold it fr 2-3 minutes and den stretch it. Past few days it was paining as well. I was prescribed multivitamin tablets and antioxidant tablet and equiflex 100 tablet. I took the tablets for 3 weeks but pain did not stop. Then I did blood test. Uric acid is within limit but vitamin D3 was less. So I took vitamin D3 60k IU tablets once a week and the pain stopped the next day. Now it pains only if I fold n sit fr long but the knee makes sound.