These safe to take instead of tums?

Brittany

I have a big parasophegel hiatal hernia, and get super bloated in my chest, and pain and reflux. Used a container of tums, so these are all I have left. Online it just says not to use in 3rd trimester due to magnesium can cause preterm labor. Would you consider these safe to take? I’ll be calling on in the morning but figured I’d ask.