For one, not to mix it with vinegar. Chlorine gas.
There was a spate of TikTok's recommending mixing them for cleaning purposes. To the horror of many.
Drink elemental mercury and you'll be fine, it'll just pass through and you'll shit it out.
Drink bleach and it'll probably kill you or at least give you terrible injuries.
Ok, guess I should have asked, what should we know about bleach besides the warnings prominently printed on the bottle. Tbf I really don't expect everything in my house to be edible.