Definition of the Ma'dhur (Excused Person) and His Ruling
Question
Zayd has an ailment of wind, that is, his wind passes very frequently and his wudu does not hold. At some times or on some days it happens that his wudu lasts up to an hour, while on other days several days pass in a row in which his wudu breaks every ten minutes or even sooner. With wind passing in this way, how should this person perform the fard prayers to be made up (qada)?
Answer
If once the full time of some prayer passes in such a state that the passing of wind is continuous, that is, it does not stop even long enough for him to make wudu and complete the prayer of that time, then this person is a ma'dhur.
Source: Fatawa Mahmudiyya
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