It's baking soda, but I haven't tried it yet.
From years of discomfort with constipation etc, I can tell you that this isn't a quick fix issue. But hey, life is to be enjoyed so we must approach this rationally with caution. For starters I am in favor of Senna tea. It is found in many laxative pills etc. Warning: when I take the tea, adding honey if you wish, depending on what I recently enjoyed eating, such as meat, then I let the tea "seep" for about 10-15 minutes, but after using for some time, about 5 minutes will do it. "IT" MEANING 7 TRIPS to the bowl within an hour. Again, careful it's a natural product widely produced in many forms, but i don't use it too consecutively. As for me, maybe once a week. I DO NOT USE ANY PRODUCT, IE: prune juice, prunes, fruits vegetables etc for more than one week straight. First time using Senna tea caused me mild cramps, sweating, but short term. I expect it, and it passes quickly.
Medical folks are working very hard for a certain fix, but it has come yet. Metamucil, Citracell doesn't work for me. My experience with natural herbs started 40 years ago with an Herbalist expert from China. Western herbalists don't "get it" in my opinion, if you have access to a visit in person to a Chinese Herbalist, you may try it...I have for other digestive problems and it works.
Some one suggested Zoloft. I researched; Zoloft MAY bring SUICIDAL thoughts...no thanks. See, that's why i stay with natural products. I am not responsible for offering any medical advice, just offering my personal experience(s) be well.