Istihadah is non-menstrual bleeding caused by a medical condition rather than the normal cycle, and jurists distinguish it from hayd by its color, consistency, and by comparing it to a woman's known regular cycle pattern. Unlike menstruation, istihadah does not exempt a woman from prayer or fasting — she is treated similarly to someone with a chronic, minor, ongoing discharge, following the guidance the Prophet ﷺ gave to women who described this condition to him. Practically, before each prayer she washes the affected area, applies a pad or protective cloth to limit the impurity from spreading, and then performs wudu; many scholars, particularly in the Hanafi school, hold this wudu remains valid through that prayer's time window and a fresh one is needed once the next prayer's time begins, regardless of whether new bleeding occurred, since the concession is tied to necessity within each window. She continues to pray, may fast, and, according to the majority of scholars, her spouse may resume marital relations with her, unlike during actual menstruation (Quran 2:222).
Q&A · Purification
How should a woman with istihadah (a medical condition causing prolonged irregular bleeding) perform wudu and pray?
References
Informational, not a personal fatwa. Consult a qualified scholar for rulings on your situation.