Could Frequent Constipation, Back Pain And Stomach Pain Be IBS, And Can Liv52 Help With IBS And Weight Gain?

Hi sir Im 24 year old girl Recently I starting getting pain in my back and stomach after i eat something or skip meal I always thought its because of gas or something And also frequently suffer from a constipation , i search through the internet and i found It s the ibs problem. Because of that im really under weight for my age , Im afraid to eat certain food And going through a lot of anxiety and depression. Pls let me know the certain medications, If you know to cure this , i really want to gain weight , and i wanted to ask is liv52 tablets is good for ibs as well as weight gain ?