What is the ruling concerning blood that continues for eleven days, with the use of a tissue internally to determine menstruation, knowing that medication is being taken which affects the regularity of menstruation, and purity is not observed despite not considering the blood found internally?

Purity must be ascertained by inserting a cotton swab only into what becomes visible when a woman sits for her needs, without inserting it deep into the vagina. What is deep inside the vagina is not considered unless it becomes visible. As for the previous menstrual period, the default is that menstruation has not ceased. As long as the questioner is unsure about its cessation before eleven days, she does not have to make up any prayers, for yellowness connected to blood is considered menstruation.