Don't know what strength they are, but I've used Tums antacid pills for adding calcium to tomatoes for years. Just put a few in a freezer bag and beat them into a powder using a hammer then mix into the soil.

and rolaids have calcium AND magnesium. tomatoes that will not cause heartburn in anybody. how 'bout that?

Feel free to crush and use them. Like the eggshell trick, they won't do anything to prevent BER but they will eventually be incorporated into the soil and doing it will make you feel better. ;)

If you will review the FAQ here on BER or some of the many discussions on it I think you'll discover that that lack of soil calcium as the cause of BER has long been disproved. It is the ability, or lack thereof, of the plant to mobilize and utilize the existing calcium in the soil. And that inability has many contributing factors as discussed in the FAQ.

Dave

Here is a link that might be useful: BER FAQ and discussions