Q: If you have a nose bleed, but the blood doesn’t come out of the nose, then does the wudu break?
A: Almost all of the books in the Hanafi Madhhab explain that, if blood exits from any part of one’s body and flows to a place upon which the command of purification applies, then one’s Wudu will be nullified.
Imam al-Quduri (Allah have mercy on him) states in his al-Mukhtasar/al-Kitab:
“(From among those things that nullify one’s wudu) is the exiting of blood and pus when they flow past the point of exit to a place upon which the command of purification applies.” (See: al-Lubab fi Sharh al-Kitab, 1/36-37) The meaning of this is that, if blood exits from one’s body and flows to a place that is required to be washed during ablution (wudu) or ritual purification bath (ghusl), then it will nullify one’s wudu.
For example, if blood exited from a cut on my hand, and flowed onto the palm of my hand, then my Wudu will be nullified, because the blood has flowed to a place (palm) that is required to be washed in both Wudu and Ghusl.
It should be remembered that, flowing of the blood will nullify one’s Wudu whether actually or effectively (such that if left un-wiped, it would have flowed).
Keeping the above explanation in mind, it becomes evident that nose-bleed also nullifies one’s Wudu. If the blood exited and flowed inside the nose to the soft part of the nose, then Wudu will be nullified. The reason being that, the washing of the inside of one’s nose is obligatory during an obligatory bath (ghusl), thus if blood flowed to a place that is required to be washed (whether in Wudu or Ghusl), then Wudu will be nullified.
However, if the blood did not flow to the soft part (bone) of the nose, then one’s Wudu will not be nullified.
And Allah Knows Best