progesterone
Pharmacologic class: Progestin
Therapeutic class: Hormone
Pregnancy risk category B (oral), D (injection),NR (vaginal)
FDA Box Warning
• Estrogen plus progestin therapy shouldn't be used for prevention of cardiovascular disease or dementia.
• The Women's Health Initiative (WHI) estrogen plus progestin substudy reported increased risk of stroke, deep vein thrombosis, pulmonary embolism, and myocardial infarction in postmenopausal women (ages 50 to 79) during 5.6 years of treatment with daily oral conjugated estrogens (0.625 mg) combined with medroxyprogesterone acetate (2.5 mg) relative to placebo.
• The substudy also demonstrated increased risk of invasive breast cancer.
• The WHI Memory Study estrogen plus progestin ancillary study of the WHI reported increased risk of dementia in postmenopausal women ages 65 and older.
Action
Suppresses ovulation by altering the vaginal epithelium, relaxing uterine smooth muscle, and promoting mammary tissue growth. Also inhibits pituitary activity and causes withdrawal bleeding in presence of estrogen.
Availability
Injection (in sesame or peanut oil with benzyl alcohol): 50 mg/ml in 10-ml vials
Micronized capsules (oral) in peanut oil: 100 mg, 200 mg
Micronized vaginal gel: 4%, 8%
Indications and dosages
➣ Secondary amenorrhea
Adults: 400 mg/day P.O. in evening for 10 days, or 5 to 10 mg/day I.M. for 6 to 8 days, given 8 to 10 days before expected menstrual period. Or 45 mg (one applicatorful of 4% gel) vaginally once every other day for up to six doses; may increase to 90 mg (one applicatorful of 8% gel) once every other day for up to six doses.
➣ Dysfunctional uterine bleeding
Adults: 5 to 10 mg I.M. daily for 6 days
➣ To prevent postmenopausal estrogen-induced endometrial hyperplasia
Adults: 200 mg/day P.O. at bedtime for 14 days on days 8 to 21 of 28-day cycle or on days 12 to 25 of 30-day cycle. If patient currently receives estrogen 1.25 mg/day, 300 mg progesterone in two divided doses (100 mg 2 hours after breakfast and 200 mg at bedtime); further adjustment may be required.
➣ Corpus luteum insufficiency; assisted reproduction technology
Adults: For luteal-phase support, 90 mg (one applicatorful of 8% gel) vaginally once daily. For in vitro fertilization, 90 mg (one applicatorful of 8% gel) vaginally once daily, starting within 24 hours of embryo transfer and continued through day 30 after transfer; if pregnancy occurs, treatment may continue for up to 12 weeks. For partial or complete ovarian failure, 90 mg (one applicatorful of 8% gel) vaginally b.i.d. while patient undergoes donor oocyte transfer; if pregnancy occurs, treatment may last up to 12 weeks.
Contraindications
• Hypersensitivity to drug, peanuts (injection, micronized capsules), or sesame (injection)
• Thromboembolic disease
• Cerebrovascular disease
• Severe hepatic disease
• Porphyria
• Breast or reproductive system cancer
• Missed abortion
• Undiagnosed vaginal bleeding
• Diagnosis of pregnancy
Precautions
Use cautiously in:
• renal or cardiovascular disease, seizure disorders, fluid retention, diabetes mellitus, asthma, migraine, depression
• history of hepatic disease
• breastfeeding patients.
Administration
• Before first dose, make sure patient has read package insert regarding adverse effects. Reinforce written information with oral review.
☞ Before first I.M. dose, ask if patient has allergy to peanuts or sesame. Before giving micronized capsules, ask about peanut allergy.
• Inject I.M. dose deep into muscle. Rotate injection sites.
Adverse reactions
CNS: depression, emotional lability, cerebrovascular accident
CV: thrombophlebitis, thromboembolism
EENT: retinal thrombosis
GI: abdominal cramps
GU: amenorrhea, breakthrough bleeding, spotting, cervical erosions, breast tenderness, menstrual flow changes, galactorrhea
Hepatic: hepatitis
Respiratory: pulmonary embolism
Skin: melasma, rash, angioedema
Other: gingival bleeding, weight gain or loss, hypersensitivity reactions including anaphylaxis
Interactions
Drug-drug. Conjugated estrogens: increased levels of both drugs
Drug-diagnostic tests. Alkaline phosphatase, amino acids, low-density lipoproteins: increased levels
Chloride and sodium excretion: reduced (with high doses)
High-density lipoproteins: decreased level
Pregnanediol excretion: reduced
Thyroid function tests: altered results
Drug-herbs. Red clover: interference with drug effects
Drug-behaviors. Smoking: increased risk of thromboembolic effects
Patient monitoring
☞ Watch for evidence of thromboembolic disorders, including cerebrovascular accident, pulmonary embolism, diplopia, proptosis, or sudden partial or complete vision loss (may signal retinal thrombosis). If these occur, discontinue drug and notify prescriber immediately.
☞ Assess for emotional lability and depression.
Patient teaching
☞ Teach patient to recognize and immediately report signs and symptoms of thromboembolic disorders.
☞ Instruct patient and significant other to stay alert for and immediately report depression.
• Advise patient to monitor weight regularly and report significant changes.
• Tell female patient that drug may cause menstrual abnormalities.
• Advise female patient to discuss breastfeeding with prescriber before taking drug.
☞ Instruct patient to immediately report possible pregnancy.
• Tell patient that smoking increases thromboembolism risk. Encourage her to stop smoking if she smokes.
• 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.