i'm 19/female and i have had IBS-C for about 5 years now and whenever i have bad stomach pains, example, when i eat the wrong foods or drink a carbinated beverage, i take about 3 or 4 extra strength tums and it stops the pain within 30 min. everytime i wake up in the middle of the night with stomach pains, tums is always there for me. so try it, and let me know how it works for u