YSK about bismuth subgallate, an "internal deodorant" that makes your stools and flatulence not smelly

Why YSK: there are times when you need to not be stinky. A multi-day outing with friends staying in one house comes to mind. Taking bismuth subgallate will make even your vilest poops and farts smell like absolutely nothing. In the US, it's FDA approved for that purpose and comes in chewable tablets.