Is one's fast valid upon waking to find blood in the mouth, and merely wiping it with a tissue without rinsing, knowing that there is constant bleeding from the gums and teeth?

If a fasting person wakes up and finds blood in their mouth and wipes it away, their fast is valid and not broken unless they intentionally swallow it. If they swallow some of it unintentionally or while asleep, their fast is valid and there is no blame upon them. As for someone from whom blood frequently flows from their mouth, they are excused, and their fast is not invalidated due to the difficulty of avoiding it.