Norethindrone Acetate(nor eth in’ drone)
Aygestin
PREGNANCY CATEGORY X
Drug Classes
Hormone
Progestin
Therapeutic Actions
Progesterone derivative. Progesterone transforms proliferative endometrium into secretory endometrium; inhibits the secretion of pituitary gonadotropins, which prevents follicular maturation and ovulation; and inhibits spontaneous uterine contraction. Progestins have varying profiles of estrogenic, antiestrogenic, anabolic, and androgenic activity.
Indications
Treatment of amenorrhea, abnormal uterine bleeding due to hormonal imbalance
Treatment of endometriosis
Base: Component of some hormonal contraceptive preparations
Contraindications and Cautions
Contraindicated with allergy to progestins; thrombophlebitis, thromboembolic disorders, cerebral hemorrhage or history of these conditions; hepatic disease; carcinoma of the breast or genital organs; undiagnosed vaginal bleeding; missed abortion; pregnancy; lactation.
Use cautiously with epilepsy, migraine, asthma, cardiac dysfunction, or renal impairment.
Available Forms
Tablets—5 mg
Dosages
Administer orally only.
Adults
Amenorrhea; abnormal uterine bleeding: 2.5–10 mg PO for 5–10 days during second half of theoretical menstrual cycle.
Endometriosis: 5 mg/day PO for 2 wk. Increase in increments of 2.5 mg/day every 2 wk until 15 mg/day is reached. May be maintained for 6–9 mo or until breakthrough bleeding demands temporary termination.
