ESTRONE
| ESTRONE (ess'trone) Classifications: hormone; estrogen; Therapeutic: estrogen; female hormone replacement therapy (hrt) Prototype: Estradiol Pregnancy Category: X |
Availability
5 mg/mL injection
Action
Estrone is one-third less active at the cellular level than estradiol, the principal premenopausal estrogen. Due to increased risk of serious complications from extended use, estrogen HRT or estrogen-progestin HRT should be prescribed for the shortest duration possible consistent with the treatment goals of post menopausal symptoms.
Therapeutic Effect
Replaces estrogen in postmenopausal women, relieving symptoms of menopause.
Uses
Atrophic vaginitis, kraurosis vulvae, and abnormal bleeding (hormonal imbalance); also female hypogonadism, primary ovarian failure, vasomotor symptoms associated with menopause, and as palliative therapy of prostatic carcinoma.
Contraindications
Breast cancer; liver dysfunction; history of thromboembolic disease; known or suspected pregnancy (category X), lactation.
Cautious Use
Hypertension; gallbladder disease; diabetes mellitus; heart failure; kidney dysfunction; seizure disorders.
Route & Dosage
| Menopause Adult: IM 0.1–0.5 mg 2–3 times/wk Female Hypogonadism, Primary Ovarian Failure Adult: IM 0.1–1 mg/wk in single or divided doses Inoperable Prostatic Cancer Palliation Adult: IM 2–4 mg/d 2–3 times/wk |
Administration
Intramuscular- Shake vial and syringe well to suspend medication before withdrawing and injecting medication.
- Give deep into a large muscle.
- Store at 15°–30° C (59°–86° F); protect from light and do not freeze.
Adverse Effects (≥1%)
CNS: Headache, dizziness, depression, libido changes. CV: Thromboembolic disorders, hypertension. GI: Nausea, vomiting, diarrhea, bloating, cholestatic jaundice. Urogenital: Mastodynia, spotting, changes in menstrual flow, dysmenorrhea, amenorrhea. Metabolic: Reduced carbohydrate tolerance, fluid retention. Other: Leg cramps, intolerance to contact lenses.Interactions
Drug: Carbamazepine, phenytoin, rifampin decrease estrogen levels because they increase metabolism; may enhance steroid effects of corticosteroids; may decrease anticoagulant effects of oral anticoagulants.Pharmacokinetics
Absorption: Occurs over several days. Metabolism: Converts to estradiol in GI mucosa. Half-Life: 4–18.5 h.Nursing Implications
Assessment & Drug Effects
- See nursing implications under estradiol.
- Monitor for and report breakthrough vaginal bleeding.
- Assess for relief of menopausal symptoms.
- Lab tests: Monitor serum phosphatase levels with prostate cancer.
- Monitor patients with conditions that may be influenced by fluid retention carefully (e.g., migraine, cardiac or kidney dysfunction, asthma, epilepsy, hypertension). Check BP on a regular basis.
- Note: Spotting or breakthrough bleeding occurring when other drugs and estrone are taken concurrently indicates reduced availability of the estrogen.
Patient & Family Education
- Review package insert to assure understanding of estrogen therapy.
- Determine weight under standard conditions 1 or 2 times/wk and report sudden weight gain or other signs of fluid retention.
- Notify physician of positive Homans' sign (calf pain upon flexing foot) and the following symptoms of thromboembolic disorders immediately: Tenderness, swelling, and redness in extremity; sudden, severe headache or chest pain; slurring of speech; change in vision; sudden shortness of breath.
- Report symptoms of vaginal candidiasis (thick, white, curd-like secretions and inflamed, congested introitus) to permit appropriate treatment.
- Notify physician of severe abdominal pain and tenderness or abdominal mass.
Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; 
Canadian drug name; 
Prototype drug