Nor-QD
norethindrone acetate
Pharmacologic class: Progesterone, hormone
Therapeutic class: Progestin
Pregnancy risk category X
Action
Inhibits pituitary gonadotropin secretion, suppressing follicular maturation and ovulation and stimulating mammary tissue growth
Availability
Tablets: 0.35 mg, 5 mg
Indications and dosages
➣ Endometriosis
Adults: 5 mg Aygestin P.O. daily for 2 weeks, increased in increments of 2.5 mg/day q 2 weeks until 15 mg daily is reached
➣ Amenorrhea; abnormal uterine bleeding
Adults: 2.5 to 10 mg Aygestin P.O. daily starting on day 5 of menstrual cycle
➣ Prevention of pregnancy
Adults: 1 tablet (0.35 mg) P.O. daily
Contraindications
• Hypersensitivity to drug
• Impaired liver function or liver disease
• Thromboembolic disorders
• Known or suspected breast cancer
• Undiagnosed vaginal bleeding
• Known or suspected pregnancy
• As a diagnostic test for pregnancy
Precautions
Use cautiously in:
• hypertension, blood dyscrasias, bone marrow disease, hepatic or renal disease, gallbladder disease, heart failure, diabetes mellitus, depression, migraine, asthma, seizure disorder
• family history of breast or reproductive tract cancer
• breastfeeding patients.
Administration
• Give with or without food.
• When administering for endometriosis, amenorrhea, or abnormal uterine bleeding, know that therapy may continue for 6 to 9 months or until breakthrough bleeding necessitates a temporary halt.
• When administering for prevention of pregnancy, know that drug must be given continuously every day at the same time with no interruptions between pill packs.
Adverse reactions
CNS: migraine, depression, insomnia, drowsiness
EENT: retinal vascular lesions, sudden partial or complete vision loss, proptosis, diplopia, papilledema
GI: nausea
GU: breakthrough bleeding, menstrual flow changes, amenorrhea, changes in cervical erosion and secretions, breast tenderness and secretion
Hepatic: cholestatic jaundice
Metabolic: fluid retention, decreased glucose tolerance
Skin: rash, urticaria, acne, hirsutism, chloasma
Other: edema, weight gain or loss, fever
Interactions
Drug-drug. Hepatic enzyme-inducing drugs (such as carbamazepine, phenobarbital, phenytoin, rifampin): decreased norethindrone efficacy
Drug-diagnostic tests. Alkaline phosphatase; amino acids; factors VII, VIII, IX, and X; nitrogen; pregnanediol: increased levels
Gamma-glutamyltransferase, high-density lipoproteins: decreased levels
Drug-herbs. Cola nut, guarana, yerba maté: increased CNS stimulation St. John's wort: decreased contraceptive efficacy
Drug-behaviors. Smoking: risk of serious cardiovascular reactions
Patient monitoring
• Monitor pretreatment and annual physical exams to check blood pressure, breasts, abdomen, pelvic organs, and Pap smear results.
Assess for signs and symptoms of depression, especially in patients with history of depression. Stop giving drug if significant depression recurs.
• Check blood glucose level in diabetic patients.
Patient teaching
• Instruct patient to avoid pregnancy or to discontinue drug if she gets pregnant (may cause serious fetal anomalies or fetal death).
Advise patient to discontinue drug and consult prescriber if she experiences sudden partial or complete vision loss.
• If patient is receiving drug to treat amenorrhea, tell her to mark administration days on calendar.
• Instruct patient taking drug to prevent pregnancy to take drug every day at the same time without interruption between pill packs.
• Tell diabetic patient to monitor blood glucose level closely and to watch for hyperglycemia.
• Instruct patient to report breakthrough bleeding, spotting, change in menstrual flow, or amenorrhea.
• Caution patient not to smoke during therapy.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs, tests, herbs, and behaviors mentioned above.