Pronunciation: nor-eth-IN-drone ASS-uh-TATE
- Tablets 5 mg
Inhibits secretion of pituitary gonadotropins, thereby preventing follicular maturation and ovulation.
Norethindrone acetate is rapidly absorbed from GI tract. T max is approximately 2 h.
Rapid distribution of dorethindrone acetate.
Norethindrone is metabolized in the liver.
Norethindrone elimination is rapid, primarily in feces.
Indications and Usage
Treatment of secondary amenorrhea; endometriosis; abnormal uterine bleeding caused by hormonal imbalance in the absence of organic pathology (eg, uterine cancer).
Thrombophlebitis, thrombolic disorders, cerebral apoplexy, or a history of these conditions; markedly impaired liver function or liver disease; known or suspected carcinoma of the breast; undiagnosed vaginal bleeding; missed abortion; as a diagnostic test for pregnancy.
Dosage and AdministrationSecondary Amenorrhea, Abnormal Uterine Bleeding
PO 2.5 to 10 mg/day for 5 to 10 days during second half of the theoretical menstrual cycle.Endometriosis
PO 5 mg/day initially for 2 wk, then increase in increments of 2.5 mg/day every 2 wk until 15 mg/day is achieved. Therapy may be continued at this level for 6 to 9 mo or until breakthrough bleeding demands temporary termination.
- Administer once daily, without regard to meals. Administer with food if GI upset occurs.
Store at controlled room temperature (59° to 86°F).
Elimination of norethindrone may be increased, decreasing the therapeutic effect.
Laboratory Test Interactions
Pregnanediol determinations may be altered; thyroid and LFT results may be affected; increased amounts of coagulation factors; reduced response to metyrapone test.
Thrombophlebitis; cerebral thrombosis and embolism; hypertension; edema.
Depression; changes in libido; changes in appetite; headache; nervousness; dizziness; fatigue.
Allergic rash; melasma; chloasma; hirsutism; alopecia; erythema multiforme; erythema nodosum; hemorrhagic eruption; itching.
Neuro-ocular lesions (eg, retinal thrombosis, optic neuritis).
Breakthrough bleeding; spotting; amenorrhea; increased cervical erosion and secretion; cystitis.
Weight gain and loss.
Premenstrual syndrome; backache.
Category X .
Excreted in breast milk.
Safety and efficacy not established.
Use with careful observation when conditions that might be affected by fluid retention are present (eg, asthma, cardiac or renal dysfunction, epilepsy).
Carefully observe patients with history of depression.
Discontinue therapy if there are any sudden changes in vision or onset of proptosis, diplopia, migraine, papilledema, or retinal vascular lesions.
- Instruct patient to take once daily as prescribed.
- Advise patient that medication can be taken without regard to meals, but to take with food if GI upset occurs.
- Warn women of childbearing potential of significant risks associated with taking this medication and becoming pregnant.
- Instruct diabetic patient to monitor blood glucose more frequently when drug is started or dose is changed and to inform health care provider of significant changes in readings.
- Instruct patient to report the following symptoms to health care provider: pain in groin or calves; sharp chest pain or sudden shortness of breath; abnormal vaginal bleeding; sudden severe headache or migraine headache; vision problems; yellowing of skin or eyes; or depression.
Copyright © 2009 Wolters Kluwer Health.