- What if someone with a mouth wound swallows blood during prayer?

Swallowing blood that comes out of a tongue wound during prayer unintentionally does not invalidate it. However, if done intentionally, it does invalidate the prayer. As for outside of prayer, if it is a small amount, there is no harm in swallowing it, though spitting it out is preferable. If it is a large amount, it is obligatory to spit it out.