Uses

Norethisterone (norethindrone) is a synthetic progestogen used to treat dysfunctional uterine bleeding, endometriosis, premenstrual syndrome, and to postpone menstruation. It is also used as a contraceptive and in hormone replacement therapy.

Do not use if

Contraindicated in patients with known or suspected pregnancy, undiagnosed vaginal bleeding, severe hepatic impairment, active thromboembolic disorders, or history of arterial or venous thrombosis. Contraindicated in patients with known or suspected hormone-dependent malignancies.

Side effects

Common side effects include irregular menstrual bleeding, breast tenderness, nausea, headache, weight changes, and mood alterations. Thromboembolic disorders, hepatic dysfunction, and androgenic effects (acne, hirsutism) may occur.

Warnings

Use with caution in patients with risk factors for cardiovascular disease or thromboembolism. Monitor hepatic function in patients on long-term therapy. Norethisterone may mask symptoms of early pregnancy. Discontinue if signs of thromboembolic disease appear.

How it works

Norethisterone is a synthetic 19-nortestosterone-derived progestogen with strong progestational activity and mild androgenic properties. It binds to progesterone receptors, suppressing ovulation and altering endometrial development to prevent implantation. It also suppresses the mid-cycle LH surge.

Storage

Store at controlled room temperature, 15°C–30°C (59°F–86°F), in a dry place away from light and moisture.