I'd be cautious with any peppermint flavored ones. Peppermint oil has side effects on its own, in large amounts. Since they're dosed for humans, I'd be careful of it with the much smaller snails. Plus, a lot of the time peppermint flavored junk will actually "burn" your mouth, imagine a snail crawling on it.
Equate Extra Strength Antacid Tablets
I haven't tried the actual Tums brand in the tanks, so I can't exactly compare them, but, the Equate (Walmart) brand started to dissolve incredibly quickly in my tanks (and my water is over 300 somethings for hardness and 8 something for pH), and one tab lasted maybe 5 minutes total. When the snails attempted to eat it, it was falling apart so fast that they gave up. Now, I'm going to assume that the Tums brand doesn't do this (or at least not as quickly) because when you try to eat them, it's almost like chewing on a rock, and the Equate brand is much softer and easier to chew. Taking them as a human, hands down, I say Equate brand, but, for snails, I don't recommend it.