Aygestin (Norethindrone acetate), also sold under the brand name Primolut Nor,  helps regulate the menstrual cycle to treat irregular periods and bleeding which is come among fertility patients. It also helps relieve endometriosis-related pain. The medication can cause breakthrough bleeding and headaches, but it might be more affordable than other alternatives for endometriosis.

Aygestin is a progestin, which is a synthetic form of the natural sex hormone progesterone. It regulates the lining of the uterus (endometrium), which then helps manage the patient’s period.

In endometriosis, abnormal endometrial tissue outside the uterus acts like the normal tissue inside the uterus. This causes pain as it grows and sheds during the menstrual cycle. Since norethindrone acetate (Aygestin) regulates endometrium, it can help ease endometriosis-related pain.

Side Effects:

Most people using this medication do not have serious side effects. Possible side effects include nausea, vomiting, headache, dizziness, mood swings, trouble sleeping, weight gain/loss, acne, breast swelling/tenderness, change in sexual interest, unwanted hair growth, or hair loss may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.

Serious side effects, including: changes in vaginal bleeding (such as spotting, breakthrough bleeding, changes in menstrual flow, no menstrual bleeding), change in vaginal discharge, depression, swelling of the hands/feet, frequent/burning/painful urination, yellowing eyes/skin, dark patches on the skin or face (melasma). This medication, especially if used with an estrogen, may rarely cause very serious problems from blood clots (such as heart attack, stroke, blood clots in the lungs, legs, or eyes). Get medical help right away if you have: chest/jaw/left arm pain, weakness on one side of the body, trouble speaking, sudden vision changes, confusion, sudden/severe headaches, sudden dizziness/fainting, shortness of breath/rapid breathing, pain/swelling/warmth in the groin/calf, unusual sweating.

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

Disclaimer: Information taken from webmd.com