Hi, Primolut-N contains norethisterone that is used to prevent unwanted pregnancies from unprotected sexual intercourses. It only contains progestin that is similar to woman s natural hormone, progesterone. It works by slowing the growth of the lining of the womb before menstruation and regulating menstrual cycles. It is a progesterone only pill that is associated with menstrual abnormalities or irregularities such as heavy menstrual bleeding, painful menstruation, endometriosis, premenstrual syndrome (PMS) etc. The normal dosage of Primolut-N is one tablet three times daily. Start taking this medication three days before the onset of expected menstrual cycle and continue for not more than 10-14 days. The patients with heavy periods or prolonged periods can take this medication for stopping their heavy or prolonged periods. Within 48 hours, bleeding will be stopped after taking this medication and your period will be shorter than usual. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Zubayer Alam, General And Family Physician