12. If a fasting person’s mouth bleeds and the blood goes down the throat, then if the amount of blood which is swallowed is equal or more than the saliva swallowed, the fast will break and only qadha will be waajib. However, if the blood is less than the saliva swallowed, the fast will not break. ^[1]

13. If a fasting person’s nose bleeds, then if the blood does not go down the nasal passage, the fast will not break. If the blood flowed down the nasal passage and entered the throat, then it will be seen whether the blood was more than the saliva or less than it. If the blood was more than the saliva or equal to it, then the fast will break. If the blood was less than the saliva, then the fast will not break. ^{[See 1]}

^[1] وإن خرج من بين أسنانه دم فابتلعه إن كان الدم غالبا على الريق أو كانا سواء أفطر ولا كفارة عليه وإن كانت الغلبة للريق لا يفطر (الجوهرة النيرة 1/141)