Yes I am on Bactrim DS 800mg twice daily. My gastroenterologist told me that the probiotic would help. Since I haven’t had any problems I believe he was correct. He gave me three brands that he thought would be best. I chose Endomune Advanced after researching the three options. It doesn’t have to be refrigerated which is helpful to me and it contains ten strains. I got mine on the health food aisle of my grocery store, but it’s also available on Amazon. Just make sure you don’t take the antibiotic and probiotic at the same time. That will decrease the effectiveness of the probiotic.