Norethindrone (also known as norethisterone) is a man-made form of progesterone, a naturally occurring female sex hormone. It is referred to as a progestin and it has a number of uses. Low doses are used to prevent pregnancy, or as hormone replacement therapy (HRT). Medium-strength tablets (5 mg) such as Aygestin® are used to treat heavy and painful menstrual periods particularly if they are associated with a condition called endometriosis. Aygestin® tablets are also used to treat endometriosis itself. Higher doses are used in the treatment of some female cancers, such as breast cancer.
This is a companion discussion topic for the original article at https://patient.info/medicine/norethindrone-for-painful-or-heavy-menstrual-periods-aygestin