Norethisterone (INN, BAN), also known as Norethindrone (USAN), is a synthetic progestational hormone with actions similar to those of progesterone but functioning as a more potent inhibitor of ovulation. It has weak estrogenic and androgenic properties. The hormone has been used in treating amenorrhea, functional uterine bleeding, endometriosis, and for contraception.
For the treatment of secondary amenorrhea, endometriosis, and abnormal uterine bleeding due to hormonal imbalance in the absence of organic pathology, such as submucous fibroids or uterine cancer.
Norethindrone is a synthetic oral progestin. It is used for contraception or to treat such conditions as secondary amenorrhea, abnormal uterine bleeding, and endometriosis. As an oral contraceptive, norethindrone is available as either a single agent or in combination with an estrogen. Norethindrone acetate induces secretory changes in an estrogen-primed endometrium. On a weight basis, it is twice as potent as norethindrone.
Mechanism of action
Progestins diffuse freely into target cells and bind to the progesterone receptor. Target cells include the female reproductive tract, the mammary gland, the hypothalamus, and the pituitary. Once bound to the receptor, progestins slow the frequency of release of gonadotropin releasing hormone (GnRH) from the hypothalamus and blunt the pre-ovulatory LH surge.
Route of administration
Chemical Actions and Uses
Contraceptive Agents, Female
Contraceptives, Oral, Synthetic
Cytochrome P-450 CYP2C19 Inducers
Cytochrome P-450 CYP3A4 Substrates
Genito Urinary System and Sex Hormones
Gonadal Steroid Hormones
Hormones, Hormone Substitutes, and Hormone Antagonists
Drug Info/Drug Targets: DrugBank 3.0: a comprehensive resource for 'omics' research on drugs. Knox C, Law V, Jewison
T, Liu P, Ly S, Frolkis A, Pon A, Banco K, Mak C, Neveu V, Djoumbou Y, Eisner R, Guo AC, Wishart DS.
Nucleic Acids Res. 2011 Jan; 39 (Database issue):D1035-41. | PMID:21059682