Effect of medicine on periods and menstrual bleeding of wife...Extended periods
Islamic ruling and solutions:
When can she offer salah?
So she should stop praying etc for the number of days that her period usually lasts every month, and this will be her menses, then she should do ghusl and pray and fast, and it is permissible to have intercourse with her, and she is taahir (pure) even though she is bleeding.
Ref: Islamqa.en/info
This is reply and answer to the query of woman whose period got extended for longer time due to medication and pill